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Diffstat (limited to 'test/ruby/pleac.in.rb')
| -rw-r--r-- | test/ruby/pleac.in.rb | 6368 |
1 files changed, 0 insertions, 6368 deletions
diff --git a/test/ruby/pleac.in.rb b/test/ruby/pleac.in.rb deleted file mode 100644 index 0f967b9..0000000 --- a/test/ruby/pleac.in.rb +++ /dev/null @@ -1,6368 +0,0 @@ -# -*- ruby -*- - -# Local variables: -# indent-tabs-mode: nil -# ruby-indent-level: 4 -# End: - -# @@PLEAC@@_NAME -# @@SKIP@@ Ruby - -# @@PLEAC@@_WEB -# @@SKIP@@ http://www.ruby-lang.org - - -# @@PLEAC@@_1.0 -string = '\n' # two characters, \ and an n -string = 'Jon \'Maddog\' Orwant' # literal single quotes - -string = "\n" # a "newline" character -string = "Jon \"Maddog\" Orwant" # literal double quotes - -string = %q/Jon 'Maddog' Orwant/ # literal single quotes - -string = %q[Jon 'Maddog' Orwant] # literal single quotes -string = %q{Jon 'Maddog' Orwant} # literal single quotes -string = %q(Jon 'Maddog' Orwant) # literal single quotes -string = %q<Jon 'Maddog' Orwant> # literal single quotes - -a = <<"EOF" -This is a multiline here document -terminated by EOF on a line by itself -EOF - - -# @@PLEAC@@_1.1 -value = string[offset,count] -value = string[offset..-1] - -string[offset,count] = newstring -string[offset..-1] = newtail - -# in Ruby we can also specify intervals by their two offsets -value = string[offset..offs2] -string[offset..offs2] = newstring - -leading, s1, s2, trailing = data.unpack("A5 x3 A8 A8 A*") - -fivers = string.unpack("A5" * (string.length/5)) - -chars = string.unpack("A1" * string.length) - -string = "This is what you have" -# +012345678901234567890 Indexing forwards (left to right) -# 109876543210987654321- Indexing backwards (right to left) -# note that 0 means 10 or 20, etc. above - -first = string[0, 1] # "T" -start = string[5, 2] # "is" -rest = string[13..-1] # "you have" -last = string[-1, 1] # "e" -end_ = string[-4..-1] # "have" -piece = string[-8, 3] # "you" - -string[5, 2] = "wasn't" # change "is" to "wasn't" -string[-12..-1] = "ondrous" # "This wasn't wondrous" -string[0, 1] = "" # delete first character -string[-10..-1] = "" # delete last 10 characters - -if string[-10..-1] =~ /pattern/ - puts "Pattern matches in last 10 characters" -end - -string[0, 5].gsub!(/is/, 'at') - -a = "make a hat" -a[0, 1], a[-1, 1] = a[-1, 1], a[0, 1] - -a = "To be or not to be" -b = a.unpack("x6 A6") - -b, c = a.unpack("x6 A2 X5 A2") -puts "#{b}\n#{c}\n" - -def cut2fmt(*args) - template = '' - lastpos = 1 - for place in args - template += "A" + (place - lastpos).to_s + " " - lastpos = place - end - template += "A*" - return template -end - -fmt = cut2fmt(8, 14, 20, 26, 30) - - -# @@PLEAC@@_1.2 -# careful! "b is true" doesn't mean "b != 0" (0 is true in Ruby) -# thus no problem of "defined" later since only nil is false -# the following sets to `c' if `b' is nil or false -a = b || c - -# if you need Perl's behaviour (setting to `c' if `b' is 0) the most -# effective way is to use Numeric#nonzero? (thanks to Dave Thomas!) -a = b.nonzero? || c - -# you will still want to use defined? in order to test -# for scope existence of a given object -a = defined?(b) ? b : c - -dir = ARGV.shift || "/tmp" - - -# @@PLEAC@@_1.3 -v1, v2 = v2, v1 - -alpha, beta, production = %w(January March August) -alpha, beta, production = beta, production, alpha - - -# @@PLEAC@@_1.4 -num = char[0] -char = num.chr - -# Ruby also supports having a char from character constant -num = ?r - -char = sprintf("%c", num) -printf("Number %d is character %c\n", num, num) - -ascii = string.unpack("C*") -string = ascii.pack("C*") - -hal = "HAL" -ascii = hal.unpack("C*") -# We can't use Array#each since we can't mutate a Fixnum -ascii.collect! { |i| - i + 1 # add one to each ASCII value -} -ibm = ascii.pack("C*") -puts ibm - - -# @@PLEAC@@_1.5 -array = string.split('') - -array = string.unpack("C*") - -string.scan(/./) { |b| - # do something with b -} - -string = "an apple a day" -print "unique chars are: ", string.split('').uniq.sort, "\n" - -sum = 0 -for ascval in string.unpack("C*") # or use Array#each for a pure OO style :) - sum += ascval -end -puts "sum is #{sum & 0xffffffff}" # since Ruby will go Bignum if necessary - -# @@INCLUDE@@ include/ruby/slowcat.rb - - -# @@PLEAC@@_1.6 -revbytes = string.reverse - -revwords = string.split(" ").reverse.join(" ") - -revwords = string.split(/(\s+)/).reverse.join - -# using the fact that IO is Enumerable, you can directly "select" it -long_palindromes = File.open("/usr/share/dict/words"). - select { |w| w.chomp!; w.reverse == w && w.length > 5 } - - -# @@PLEAC@@_1.7 -while string.sub!("\t+") { ' ' * ($&.length * 8 - $`.length % 8) } -end - - -# @@PLEAC@@_1.8 -'You owe #{debt} to me'.gsub(/\#{(\w+)}/) { eval($1) } - -rows, cols = 24, 80 -text = %q(I am #{rows} high and #{cols} long) -text.gsub!(/\#{(\w+)}/) { eval("#{$1}") } -puts text - -'I am 17 years old'.gsub(/\d+/) { 2 * $&.to_i } - - -# @@PLEAC@@_1.9 -e = "bo peep".upcase -e.downcase! -e.capitalize! - -"thIS is a loNG liNE".gsub!(/\w+/) { $&.capitalize } - - -# @@PLEAC@@_1.10 -"I have #{n+1} guanacos." -print "I have ", n+1, " guanacos." - - -# @@PLEAC@@_1.11 -var = <<'EOF'.gsub(/^\s+/, '') - your text - goes here -EOF - - -# @@PLEAC@@_1.12 -string = "Folding and splicing is the work of an editor,\n"+ - "not a mere collection of silicon\n"+ - "and\n"+ - "mobile electrons!" - -def wrap(str, max_size) - all = [] - line = '' - for l in str.split - if (line+l).length >= max_size - all.push(line) - line = '' - end - line += line == '' ? l : ' ' + l - end - all.push(line).join("\n") -end - -print wrap(string, 20) -#=> Folding and -#=> splicing is the -#=> work of an editor, -#=> not a mere -#=> collection of -#=> silicon and mobile -#=> electrons! - - -# @@PLEAC@@_1.13 -string = %q(Mom said, "Don't do that.") -string.gsub(/['"]/) { '\\'+$& } -string.gsub(/['"]/, '\&\&') -string.gsub(/[^A-Z]/) { '\\'+$& } -"is a test!".gsub(/\W/) { '\\'+$& } # no function like quotemeta? - - -# @@PLEAC@@_1.14 -string.strip! - - -# @@PLEAC@@_1.15 -def parse_csv(text) - new = text.scan(/"([^\"\\]*(?:\\.[^\"\\]*)*)",?|([^,]+),?|,/) - new << nil if text[-1] == ?, - new.flatten.compact -end - -line = %q<XYZZY,"","O'Reilly, Inc","Wall, Larry","a \"glug\" bit,",5,"Error, Core Dumped"> -fields = parse_csv(line) -fields.each_with_index { |v,i| - print "#{i} : #{v}\n"; -} - - -# @@PLEAC@@_1.16 -# Use the soundex.rb Library from Michael Neumann. -# http://www.s-direktnet.de/homepages/neumann/rb_prgs/Soundex.rb -require 'Soundex' - -code = Text::Soundex.soundex(string) -codes = Text::Soundex.soundex(array) - -# substitution function for getpwent(): -# returns an array of user entries, -# each entry contains the username and the full name -def login_names - result = [] - File.open("/etc/passwd") { |file| - file.each_line { |line| - next if line.match(/^#/) - cols = line.split(":") - result.push([cols[0], cols[4]]) - } - } - result -end - -puts "Lookup user: " -user = STDIN.gets -user.chomp! -exit unless user -name_code = Text::Soundex.soundex(user) - -splitter = Regexp.new('(\w+)[^,]*\b(\w+)') -for username, fullname in login_names do - firstname, lastname = splitter.match(fullname)[1,2] - if name_code == Text::Soundex.soundex(username) - || name_code == Text::Soundex.soundex(firstname) - || name_code == Text::Soundex.soundex(lastname) - then - puts "#{username}: #{firstname} #{lastname}" - end -end - - -# @@PLEAC@@_1.17 -# @@INCLUDE@@ include/ruby/fixstyle.rb - - -# @@PLEAC@@_1.18 -# @@INCLUDE@@ include/ruby/psgrep.rb - - -# @@PLEAC@@_2.1 -# Matz tells that you can use Integer() for strict checked conversion. -Integer("abc") -#=> `Integer': invalid value for Integer: "abc" (ArgumentError) -Integer("567") -#=> 567 - -# You may use Float() for floating point stuff -Integer("56.7") -#=> `Integer': invalid value for Integer: "56.7" (ArgumentError) -Float("56.7") -#=> 56.7 - -# You may also use a regexp for that -if string =~ /^[+-]?\d+$/ - p 'is an integer' -else - p 'is not' -end - -if string =~ /^-?(?:\d+(?:\.\d*)?|\.\d+)$/ - p 'is a decimal number' -else - p 'is not' -end - - -# @@PLEAC@@_2.2 -# equal(num1, num2, accuracy) : returns true if num1 and num2 are -# equal to accuracy number of decimal places -def equal(i, j, a) - sprintf("%.#{a}g", i) == sprintf("%.#{a}g", j) -end - -wage = 536 # $5.36/hour -week = 40 * wage # $214.40 -printf("One week's wage is: \$%.2f\n", week/100.0) - - -# @@PLEAC@@_2.3 -num.round # rounds to integer - -a = 0.255 -b = sprintf("%.2f", a) -print "Unrounded: #{a}\nRounded: #{b}\n" -printf "Unrounded: #{a}\nRounded: %.2f\n", a - -print "number\tint\tfloor\tceil\n" -a = [ 3.3 , 3.5 , 3.7, -3.3 ] -for n in a - printf("% .1f\t% .1f\t% .1f\t% .1f\n", # at least I don't fake my output :) - n, n.to_i, n.floor, n.ceil) -end - - -# @@PLEAC@@_2.4 -def dec2bin(n) - [n].pack("N").unpack("B32")[0].sub(/^0+(?=\d)/, '') -end - -def bin2dec(n) - [("0"*32+n.to_s)[-32..-1]].pack("B32").unpack("N")[0] -end - - -# @@PLEAC@@_2.5 -for i in x .. y - # i is set to every integer from x to y, inclusive -end - -x.step(y,7) { |i| - # i is set to every integer from x to y, stepsize = 7 -} - -print "Infancy is: " -(0..2).each { |i| - print i, " " -} -print "\n" - - -# @@PLEAC@@_2.6 -# We can add conversion methods to the Integer class, -# this makes a roman number just a representation for normal numbers. -class Integer - - @@romanlist = [["M", 1000], - ["CM", 900], - ["D", 500], - ["CD", 400], - ["C", 100], - ["XC", 90], - ["L", 50], - ["XL", 40], - ["X", 10], - ["IX", 9], - ["V", 5], - ["IV", 4], - ["I", 1]] - - def to_roman - remains = self - roman = "" - for sym, num in @@romanlist - while remains >= num - remains -= num - roman << sym - end - end - roman - end - - def Integer.from_roman(roman) - ustr = roman.upcase - sum = 0 - for entry in @@romanlist - sym, num = entry[0], entry[1] - while sym == ustr[0, sym.length] - sum += num - ustr.slice!(0, sym.length) - end - end - sum - end - -end - - -roman_fifteen = 15.to_roman -puts "Roman for fifteen is #{roman_fifteen}" -i = Integer.from_roman(roman_fifteen) -puts "Converted back, #{roman_fifteen} is #{i}" - -# check -for i in (1..3900) - r = i.to_roman - j = Integer.from_roman(r) - if i != j - puts "error: #{i} : #{r} - #{j}" - end -end - - -# @@PLEAC@@_2.7 -random = rand(y-x+1)+x - -chars = ["A".."Z","a".."z","0".."9"].collect { |r| r.to_a }.join + %q(!@$%^&*) -password = (1..8).collect { chars[rand(chars.size)] }.pack("C*") - - -# @@PLEAC@@_2.8 -srand # uses a combination of the time, the process id, and a sequence number -srand(val) # for repeatable behaviour - - -# @@PLEAC@@_2.9 -# from the randomr lib: -# http://raa.ruby-lang.org/project/randomr/ -----> http://raa.ruby-lang.org/project/randomr/ - -require 'random/mersenne_twister' -mers = Random::MersenneTwister.new 123456789 -puts mers.rand(0) # 0.550321932544541 -puts mers.rand(10) # 2 - -# using online sources of random data via the realrand package: -# http://raa.ruby-lang.org/project/realrand/ -# **Note** -# The following online services are used in this package: -# http://www.random.org - source: atmospheric noise -# http://www.fourmilab.ch/hotbits - source: radioactive decay timings -# http://random.hd.org - source: entropy from local and network noise -# Please visit the sites and respect the rules of each service. - -require 'random/online' - -generator1 = Random::RandomOrg.new -puts generator1.randbyte(5).join(",") -puts generator1.randnum(10, 1, 6).join(",") # Roll dice 10 times. - -generator2 = Random::FourmiLab.new -puts generator2.randbyte(5).join(",") -# randnum is not supported. - -generator3 = Random::EntropyPool.new -puts generator3.randbyte(5).join(",") -# randnum is not supported. - - -# @@PLEAC@@_2.10 -def gaussian_rand - begin - u1 = 2 * rand() - 1 - u2 = 2 * rand() - 1 - w = u1*u1 + u2*u2 - end while (w >= 1) - w = Math.sqrt((-2*Math.log(w))/w) - [ u2*w, u1*w ] -end - -mean = 25 -sdev = 2 -salary = gaussian_rand[0] * sdev + mean -printf("You have been hired at \$%.2f\n", salary) - - -# @@PLEAC@@_2.11 -def deg2rad(d) - (d/180.0)*Math::PI -end - -def rad2deg(r) - (r/Math::PI)*180 -end - - -# @@PLEAC@@_2.12 -sin_val = Math.sin(angle) -cos_val = Math.cos(angle) -tan_val = Math.tan(angle) - -# AFAIK Ruby's Math module doesn't provide acos/asin -# While we're at it, let's also define missing hyperbolic functions -module Math - def Math.asin(x) - atan2(x, sqrt(1 - x**2)) - end - def Math.acos(x) - atan2(sqrt(1 - x**2), x) - end - def Math.atan(x) - atan2(x, 1) - end - def Math.sinh(x) - (exp(x) - exp(-x)) / 2 - end - def Math.cosh(x) - (exp(x) + exp(-x)) / 2 - end - def Math.tanh(x) - sinh(x) / cosh(x) - end -end - -# The support for Complex numbers is not built-in -y = Math.acos(3.7) -#=> in `sqrt': square root for negative number (ArgumentError) - -# There is an implementation of Complex numbers in 'complex.rb' in current -# Ruby distro, but it doesn't support atan2 with complex args, so it doesn't -# solve this problem. - - -# @@PLEAC@@_2.13 -log_e = Math.log(val) -log_10 = Math.log10(val) - -def log_base(base, val) - Math.log(val)/Math.log(base) -end - -answer = log_base(10, 10_000) -puts "log10(10,000) = #{answer}" - - -# @@PLEAC@@_2.14 -require 'matrix.rb' - -a = Matrix[[3, 2, 3], [5, 9, 8]] -b = Matrix[[4, 7], [9, 3], [8, 1]] -c = a * b - -a.row_size -a.column_size - -c.det -a.transpose - - -# @@PLEAC@@_2.15 -require 'complex.rb' -require 'rational.rb' - -a = Complex(3, 5) # 3 + 5i -b = Complex(2, -2) # 2 - 2i -puts "c = #{a*b}" - -c = a * b -d = 3 + 4*Complex::I - -printf "sqrt(#{d}) = %s\n", Math.sqrt(d) - - -# @@PLEAC@@_2.16 -number = hexadecimal.hex -number = octal.oct - -print "Gimme a number in decimal, octal, or hex: " -num = gets.chomp -exit unless defined?(num) -num = num.oct if num =~ /^0/ # does both oct and hex -printf "%d %x %o\n", num, num, num - -print "Enter file permission in octal: " -permissions = gets.chomp -raise "Exiting ...\n" unless defined?(permissions) -puts "The decimal value is #{permissions.oct}" - - -# @@PLEAC@@_2.17 -def commify(n) - n.to_s =~ /([^\.]*)(\..*)?/ - int, dec = $1.reverse, $2 ? $2 : "" - while int.gsub!(/(,|\.|^)(\d{3})(\d)/, '\1\2,\3') - end - int.reverse + dec -end - - -# @@PLEAC@@_2.18 -printf "It took %d hour%s\n", time, time == 1 ? "" : "s" - -# dunno if an equivalent to Lingua::EN::Inflect exists... - - -# @@PLEAC@@_2.19 -#----------------------------- -#!/usr/bin/ruby -# bigfact - calculating prime factors -def factorize(orig) - factors = {} - factors.default = 0 # return 0 instead nil if key not found in hash - n = orig - i = 2 - sqi = 4 # square of i - while sqi <= n do - while n.modulo(i) == 0 do - n /= i - factors[i] += 1 - # puts "Found factor #{i}" - end - # we take advantage of the fact that (i +1)**2 = i**2 + 2*i +1 - sqi += 2 * i + 1 - i += 1 - end - - if (n != 1) && (n != orig) - factors[n] += 1 - end - factors -end - -def printfactorhash(orig, factorcount) - print format("%-10d ", orig) - if factorcount.length == 0 - print "PRIME" - else - # sorts after number, because the hash keys are numbers - factorcount.sort.each { |factor,exponent| - print factor - if exponent > 1 - print "**", exponent - end - print " " - } - end - puts -end - -for arg in ARGV - n = arg.to_i - mfactors = factorize(n) - printfactorhash(n, mfactors) -end -#----------------------------- - - -# @@PLEAC@@_3.0 -puts Time.now - -print "Today is day ", Time.now.yday, " of the current year.\n" -print "Today is day ", Time.now.day, " of the current month.\n" - - -# @@PLEAC@@_3.1 -day, month, year = Time.now.day, Time.now.month, Time.now.year -# or -day, month, year = Time.now.to_a[3..5] - -tl = Time.now.localtime -printf("The current date is %04d %02d %02d\n", tl.year, tl.month, tl.day) - -Time.now.localtime.strftime("%Y-%m-%d") - - -# @@PLEAC@@_3.2 -Time.local(year, month, day, hour, minute, second).tv_sec -Time.gm(year, month, day, hour, minute, second).tv_sec - - -# @@PLEAC@@_3.3 -sec, min, hour, day, month, year, wday, yday, isdst, zone = Time.at(epoch_secs).to_a - - -# @@PLEAC@@_3.4 -when_ = now + difference # now -> Time ; difference -> Numeric (delta in seconds) -then_ = now - difference - - -# @@PLEAC@@_3.5 -bree = 361535725 -nat = 96201950 - -difference = bree - nat -puts "There were #{difference} seconds between Nat and Bree" - -seconds = difference % 60 -difference = (difference - seconds) / 60 -minutes = difference % 60 -difference = (difference - minutes) / 60 -hours = difference % 24 -difference = (difference - hours) / 24 -days = difference % 7 -weeks = (difference - days) / 7 - -puts "(#{weeks} weeks, #{days} days, #{hours}:#{minutes}:#{seconds})" - - -# @@PLEAC@@_3.6 -monthday, weekday, yearday = date.mday, date.wday, date.yday - -# AFAIK the week number is not just a division since week boundaries are on sundays -weeknum = d.strftime("%U").to_i + 1 - -year = 1981 -month = "jun" # or `6' if you want to emulate a broken language -day = 16 -t = Time.mktime(year, month, day) -print "#{month}/#{day}/#{year} was a ", t.strftime("%A"), "\n" - - -# @@PLEAC@@_3.7 -yyyy, mm, dd = $1, $2, $3 if "1998-06-25" =~ /(\d+)-(\d+)-(\d+)/ - -epoch_seconds = Time.mktime(yyyy, mm, dd).tv_sec - -# dunno an equivalent to Date::Manip#ParseDate - - -# @@PLEAC@@_3.8 -string = Time.at(epoch_secs) -Time.at(1234567890).gmtime # gives: Fri Feb 13 23:31:30 UTC 2009 - -time = Time.mktime(1973, "jan", 18, 3, 45, 50) -print "In localtime it gives: ", time.localtime, "\n" - - -# @@PLEAC@@_3.9 -# Ruby provides micro-seconds in Time object -Time.now.usec - -# Ruby gives the seconds in floating format when substracting two Time objects -before = Time.now -line = gets -elapsed = Time.now - before -puts "You took #{elapsed} seconds." - -# On my Celeron-400 with Linux-2.2.19-14mdk, average for three execs are: -# This Ruby version: average 0.00321 sec -# Cookbook's Perl version: average 0.00981 sec -size = 500 -number_of_times = 100 -total_time = 0 -number_of_times.times { - # populate array - array = [] - size.times { array << rand } - # sort it - begin_ = Time.now - array.sort! - time = Time.now - begin_ - total_time += time -} -printf "On average, sorting %d random numbers takes %.5f seconds\n", - size, (total_time/Float(number_of_times)) - - -# @@PLEAC@@_3.10 -sleep(0.005) # Ruby is definitely not as broken as Perl :) -# (may be interrupted by sending the process a SIGALRM) - - -# @@PLEAC@@_3.11 -#!/usr/bin/ruby -w -# hopdelta - feed mail header, produce lines -# showing delay at each hop. -require 'time' -class MailHopDelta - - def initialize(mail) - @head = mail.gsub(/\n\s+/,' ') - @topline = %w-Sender Recipient Time Delta- - @start_from = mail.match(/^From.*\@([^\s>]*)/)[1] - @date = Time.parse(mail.match(/^Date:\s+(.*)/)[1]) - end - - def out(line) - "%-20.20s %-20.20s %-20.20s %s" % line - end - - def hop_date(day) - day.strftime("%I:%M:%S %Y/%m/%d") - end - - def puts_hops - puts out(@topline) - puts out(['Start', @start_from, hop_date(@date),'']) - @head.split(/\n/).reverse.grep(/^Received:/).each do |hop| - hop.gsub!(/\bon (.*?) (id.*)/,'; \1') - whence = hop.match(/;\s+(.*)$/)[1] - unless whence - warn "Bad received line: #{hop}" - next - end - from = $+ if hop =~ /from\s+(\S+)|\((.*?)\)/ - by = $1 if hop =~ /by\s+(\S+\.\S+)/ - next unless now = Time.parse(whence).localtime - delta = now - @date - puts out([from, by, hop_date(now), hop_time(delta)]) - @date = now - end - end - - def hop_time(secs) - sign = secs < 0 ? -1 : 1 - days, secs = secs.abs.divmod(60 * 60 * 24) - hours,secs = secs.abs.divmod(60 * 60) - mins, secs = secs.abs.divmod(60) - rtn = "%3ds" % [secs * sign] - rtn << "%3dm" % [mins * sign] if mins != 0 - rtn << "%3dh" % [hours * sign] if hours != 0 - rtn << "%3dd" % [days * sign] if days != 0 - rtn - end -end - -$/ = "" -mail = MailHopDelta.new(ARGF.gets).puts_hops - - -# @@PLEAC@@_4.0 -single_level = [ "this", "that", "the", "other" ] - -# Ruby directly supports nested arrays -double_level = [ "this", "that", [ "the", "other" ] ] -still_single_level = [ "this", "that", [ "the", "other" ] ].flatten - - -# @@PLEAC@@_4.1 -a = [ "quick", "brown", "fox" ] -a = %w(Why are you teasing me?) - -lines = <<"END_OF_HERE_DOC".gsub(/^\s*(.+)/, '\1') - The boy stood on the burning deck, - It was as hot as glass. -END_OF_HERE_DOC - -bigarray = IO.readlines("mydatafile").collect { |l| l.chomp } - -name = "Gandalf" -banner = %Q(Speak, #{name}, and welcome!) - -host_info = `host #{his_host}` - -%x(ps #{$$}) - -banner = 'Costs only $4.95'.split(' ') - -rax = %w! ( ) < > { } [ ] ! - - -# @@PLEAC@@_4.2 -def commify_series(arr) - return '' if not arr - case arr.size - when 0 then '' - when 1 then arr[0] - when 2 then arr.join(' and ') - else arr[0..-2].join(', ') + ', and ' + arr[-1] - end -end - -array = [ "red", "yellow", "green" ] - -print "I have ", array, " marbles\n" -# -> I have redyellowgreen marbles - -# But unlike Perl: -print "I have #{array} marbles\n" -# -> I have redyellowgreen marbles -# So, needs: -print "I have #{array.join(' ')} marbles\n" -# -> I have red yellow green marbles - -#!/usr/bin/ruby -# communify_series - show proper comma insertion in list output - -def commify_series(arr) - return '' if not arr - sepchar = arr.find { |p| p =~ /,/ } ? '; ' : ', ' - case arr.size - when 0 then '' - when 1 then arr[0] - when 2 then arr.join(' and ') - else arr[0..-2].join(sepchar) + sepchar + 'and ' + arr[-1] - end -end - -lists = [ - [ 'just one thing' ], - %w(Mutt Jeff), - %w(Peter Paul Mary), - [ 'To our parents', 'Mother Theresa', 'God' ], - [ 'pastrami', 'ham and cheese', 'peanut butter and jelly', 'tuna' ], - [ 'recycle tired, old phrases', 'ponder big, happy thoughts' ], - [ 'recycle tired, old phrases', - 'ponder big, happy thoughts', - 'sleep and dream peacefully' ], -] - -for list in lists do - puts "The list is: #{commify_series(list)}." -end - - -# @@PLEAC@@_4.3 -# (note: AFAIK Ruby doesn't allow gory change of Array length) -# grow the array by assigning nil to past the end of array -ary[new_size-1] = nil -# shrink the array by slicing it down -ary.slice!(new_size..-1) -# init the array with given size -Array.new(number_of_elems) -# assign to an element past the original end enlarges the array -ary[index_new_last_elem] = value - -def what_about_that_array(a) - print "The array now has ", a.size, " elements.\n" - # Index of last element is not really interesting in Ruby - print "Element #3 is `#{a[3]}'.\n" -end -people = %w(Crosby Stills Nash Young) -what_about_that_array(people) - - -# @@PLEAC@@_4.4 -# OO style -bad_users.each { |user| - complain(user) -} -# or, functional style -for user in bad_users - complain(user) -end - -for var in ENV.keys.sort - puts "#{var}=#{ENV[var]}" -end - -for user in all_users - disk_space = get_usage(user) - if (disk_space > MAX_QUOTA) - complain(user) - end -end - -for l in IO.popen("who").readlines - print l if l =~ /^gc/ -end - -# we can mimic the obfuscated Perl way -while fh.gets # $_ is set to the line just read - chomp # $_ has a trailing \n removed, if it had one - split.each { |w| # $_ is split on whitespace - # but $_ is not set to each chunk as in Perl - print w.reverse - } -end -# ...or use a cleaner way -for l in fh.readlines - l.chomp.split.each { |w| print w.reverse } -end - -# same drawback as in problem 1.4, we can't mutate a Numeric... -array.collect! { |v| v - 1 } - -a = [ .5, 3 ]; b = [ 0, 1 ] -for ary in [ a, b ] - ary.collect! { |v| v * 7 } -end -puts "#{a.join(' ')} #{b.join(' ')}" - -# we can mutate Strings, cool; we need a trick for the scalar -for ary in [ [ scalar ], array, hash.values ] - ary.each { |v| v.strip! } # String#strip rules :) -end - - -# @@PLEAC@@_4.5 -# not relevant in Ruby since we have always references -for item in array - # do somethingh with item -end - - -# @@PLEAC@@_4.6 -unique = list.uniq - -# generate a list of users logged in, removing duplicates -users = `who`.collect { |l| l =~ /(\w+)/; $1 }.sort.uniq -puts("users logged in: #{commify_series(users)}") # see 4.2 for commify_series - - -# @@PLEAC@@_4.7 -a - b -# [ 1, 1, 2, 2, 3, 3, 3, 4, 5 ] - [ 1, 2, 4 ] -> [3, 5] - - -# @@PLEAC@@_4.8 -union = a | b -intersection = a & b -difference = a - b - - -# @@PLEAC@@_4.9 -array1.concat(array2) -# if you will assign to another object, better use: -new_ary = array1 + array2 - -members = [ "Time", "Flies" ] -initiates = [ "An", "Arrow" ] -members += initiates - -members = [ "Time", "Flies" ] -initiates = [ "An", "Arrow" ] -members[2,0] = [ "Like", initiates ].flatten - -members[0] = "Fruit" -members[3,2] = "A", "Banana" - - -# @@PLEAC@@_4.10 -reversed = ary.reverse - -ary.reverse_each { |e| - # do something with e -} - -descending = ary.sort.reverse -descending = ary.sort { |a,b| b <=> a } - - -# @@PLEAC@@_4.11 -# remove n elements from front of ary (shift n) -front = ary.slice!(0, n) - -# remove n elements from the end of ary (pop n) -end_ = ary.slice!(-n .. -1) - -# let's extend the Array class, to make that useful -class Array - def shift2() - slice!(0 .. 1) # more symetric with pop2... - end - def pop2() - slice!(-2 .. -1) - end -end - -friends = %w(Peter Paul Mary Jim Tim) -this, that = friends.shift2 - -beverages = %w(Dew Jolt Cola Sprite Fresca) -pair = beverages.pop2 - - -# @@PLEAC@@_4.12 -# use Enumerable#detect (or the synonym Enumerable#find) -highest_eng = employees.detect { |emp| emp.category == 'engineer' } - - -# @@PLEAC@@_4.13 -# use Enumerable#select (or the synonym Enumerable#find_all) -bigs = nums.select { |i| i > 1_000_000 } -pigs = users.keys.select { |k| users[k] > 1e7 } - -matching = `who`.select { |u| u =~ /^gnat / } - -engineers = employees.select { |e| e.position == 'Engineer' } - -secondary_assistance = applicants.select { |a| - a.income >= 26_000 && a.income < 30_000 -} - - -# @@PLEAC@@_4.14 -# normally you would have an array of Numeric (Float or -# Fixnum or Bignum), so you would use: -sorted = unsorted.sort -# if you have strings representing Integers or Floats -# you may specify another sort method: -sorted = unsorted.sort { |a,b| a.to_f <=> b.to_f } - -# let's use the list of my own PID's -`ps ux`.split("\n")[1..-1]. - select { |i| i =~ /^#{ENV['USER']}/ }. - collect { |i| i.split[1] }. - sort { |a,b| a.to_i <=> b.to_i }.each { |i| puts i } -puts "Select a process ID to kill:" -pid = gets.chomp -raise "Exiting ... \n" unless pid && pid =~ /^\d+$/ -Process.kill('TERM', pid.to_i) -sleep 2 -Process.kill('KILL', pid.to_i) - -descending = unsorted.sort { |a,b| b.to_f <=> a.to_f } - - -# @@PLEAC@@_4.15 -ordered = unordered.sort { |a,b| compare(a,b) } - -precomputed = unordered.collect { |e| [compute, e] } -ordered_precomputed = precomputed.sort { |a,b| a[0] <=> b[0] } -ordered = ordered_precomputed.collect { |e| e[1] } - -ordered = unordered.collect { |e| [compute, e] }. - sort { |a,b| a[0] <=> b[0] }. - collect { |e| e[1] } - -for employee in employees.sort { |a,b| a.name <=> b.name } - print employee.name, " earns \$ ", employee.salary, "\n" -end - -# Beware! `0' is true in Ruby. -# For chaining comparisons, you may use Numeric#nonzero?, which -# returns num if num is not zero, nil otherwise -sorted = employees.sort { |a,b| (a.name <=> b.name).nonzero? || b.age <=> a.age } - -users = [] -# getpwent is not wrapped in Ruby... let's fallback -IO.readlines('/etc/passwd').each { |u| users << u.split(':') } -users.sort! { |a,b| a[0] <=> b[0] } -for user in users - puts user[0] -end - -sorted = names.sort { |a,b| a[1, 1] <=> b[1, 1] } -sorted = strings.sort { |a,b| a.length <=> b.length } - -# let's show only the compact version -ordered = strings.collect { |e| [e.length, e] }. - sort { |a,b| a[0] <=> b[0] }. - collect { |e| e[1] } - -ordered = strings.collect { |e| [/\d+/.match(e)[0].to_i, e] }. - sort { |a,b| a[0] <=> b[0] }. - collect { |e| e[1] } - -print `cat /etc/passwd`.collect { |e| [e, e.split(':').indexes(3,2,0)].flatten }. - sort { |a,b| (a[1] <=> b[1]).nonzero? || (a[2] <=> b[2]).nonzero? || a[3] <=> b[3] }. - collect { |e| e[0] } - - -# @@PLEAC@@_4.16 -circular.unshift(circular.pop) # the last shall be first -circular.push(circular.shift) # and vice versa - -def grab_and_rotate(l) - l.push(ret = l.shift) - ret -end - -processes = [1, 2, 3, 4, 5] -while (1) - process = grab_and_rotate(processes) - puts "Handling process #{process}" - sleep 1 -end - - -# @@PLEAC@@_4.17 -def fisher_yates_shuffle(a) - (a.size-1).downto(1) { |i| - j = rand(i+1) - a[i], a[j] = a[j], a[i] if i != j - } -end - -def naive_shuffle(a) - for i in 0...a.size - j = rand(a.size) - a[i], a[j] = a[j], a[i] - end -end - - -# @@PLEAC@@_4.18 -#!/usr/bin/env ruby -# example 4-2 words -# words - gather lines, present in colums - -# class to encapsulate the word formatting from the input -class WordFormatter - def initialize(cols) - @cols = cols - end - - # helper to return the length of the longest word in the wordlist - def maxlen(wordlist) - max = 1 - for word in wordlist - if word.length > max - max = word.length - end - end - max - end - - # process the wordlist and print it formmated into columns - def output(wordlist) - collen = maxlen(wordlist) + 1 - columns = @cols / collen - columns = 1 if columns == 0 - rows = (wordlist.length + columns - 1) / columns - # now process each item, picking out proper piece for this position - 0.upto(rows * columns - 1) { |item| - target = (item % columns) * rows + (item / columns) - eol = ((item+1) % columns == 0) - piece = wordlist[target] || "" - piece = piece.ljust(collen) unless eol - print piece - puts if eol - } - # no need to finish it up, because eol is always true for the last element - end -end - -# get nr of chars that fit in window or console, see PLEAC 15.4 -# not portable -- linux only (?) -def getWinCharWidth() - buf = "\0" * 8 - $stdout.ioctl(0x5413, buf) - ws_row, ws_col, ws_xpixel, ws_ypixel = buf.unpack("$4") - ws_col || 80 -rescue - 80 -end - -# main program -cols = getWinCharWidth() -formatter = WordFormatter.new(cols) -words = readlines() -words.collect! { |line| - line.chomp -} -formatter.output(words) - - -# @@PLEAC@@_4.19 -# In ruby, Fixnum's are automatically converted to Bignum's when -# needed, so there is no need for an extra module -def factorial(n) - s = 1 - while n > 0 - s *= n - n -= 1 - end - s -end - -puts factorial(500) - -#--------------------------------------------------------- -# Example 4-3. tsc-permute -# tsc_permute: permute each word of input -def permute(items, perms) - unless items.length > 0 - puts perms.join(" ") - else - for i in items - newitems = items.dup - newperms = perms.dup - newperms.unshift(newitems.delete(i)) - permute(newitems, newperms) - end - end -end -# In ruby the main program must be after all definitions it is using -permute(ARGV, []) - -#--------------------------------------------------------- -# mjd_permute: permute each word of input - -def factorial(n) - s = 1 - while n > 0 - s *= n - n -= 1 - end - s -end - -# we use a class with a class variable store the private cache -# for the results of the factorial function. -class Factorial - @@fact = [ 1 ] - def Factorial.compute(n) - if @@fact[n] - @@fact[n] - else - @@fact[n] = n * Factorial.compute(n - 1) - end - end -end - -#--------------------------------------------------------- -# Example 4-4- mjd-permute -# n2pat(n, len): produce the N-th pattern of length len - -# We must use a lower case letter as parameter N, otherwise it is -# handled as constant Length is the length of the resulting -# array, not the index of the last element (length -1) like in -# the perl example. -def n2pat(n, length) - pat = [] - i = 1 - while i <= length - pat.push(n % i) - n /= i - i += 1 - end - pat -end - -# pat2perm(pat): turn pattern returned by n2pat() into -# permutation of integers. -def pat2perm(pat) - source = (0 .. pat.length - 1).to_a - perm = [] - perm.push(source.slice!(pat.pop)) while pat.length > 0 - perm -end - -def n2perm(n, len) - pat2perm(n2pat(n,len)) -end - -# In ruby the main program must be after all definitions -while gets - data = split - # the perl solution has used $#data, which is length-1 - num_permutations = Factorial.compute(data.length()) - 0.upto(num_permutations - 1) do |i| - # in ruby we can not use an array as selector for an array - # but by exchanging the two arrays, we can use the collect method - # which returns an array with the result of all block invocations - permutation = n2perm(i, data.length).collect { - |j| data[j] - } - puts permutation.join(" ") - end -end - - -# @@PLEAC@@_5.0 -age = { "Nat", 24, - "Jules", 25, - "Josh", 17 } - -age["Nat"] = 24 -age["Jules"] = 25 -age["Josh"] = 17 - -food_color = { - "Apple" => "red", - "Banana" => "yellow", - "Lemon" => "yellow", - "Carrot" => "orange" - } - -# In Ruby, you cannot avoid the double or simple quoting -# while manipulatin hashes - - -# @@PLEAC@@_5.1 -hash[key] = value - -food_color["Raspberry"] = "pink" -puts "Known foods:", food_color.keys - - -# @@PLEAC@@_5.2 -# does hash have a value for key ? -if (hash.has_key?(key)) - # it exists -else - # it doesn't -end - -[ "Banana", "Martini" ].each { |name| - print name, " is a ", food_color.has_key?(name) ? "food" : "drink", "\n" -} - -age = {} -age['Toddler'] = 3 -age['Unborn'] = 0 -age['Phantasm'] = nil - -for thing in ['Toddler', 'Unborn', 'Phantasm', 'Relic'] - print "#{thing}: " - print "Has-key " if age.has_key?(thing) - print "True " if age[thing] - print "Nonzero " if age[thing] && age[thing].nonzero? - print "\n" -end - -#=> -# Toddler: Has-key True Nonzero -# Unborn: Has-key True -# Phantasm: Has-key -# Relic: - -# You use Hash#has_key? when you use Perl's exists -> it checks -# for existence of a key in a hash. -# All Numeric are "True" in ruby, so the test doesn't have the -# same semantics as in Perl; you would use Numeric#nonzero? to -# achieve the same semantics (false if 0, true otherwise). - - -# @@PLEAC@@_5.3 -food_color.delete("Banana") - - -# @@PLEAC@@_5.4 -hash.each { |key, value| - # do something with key and value -} - -hash.each_key { |key| - # do something with key -} - -food_color.each { |food, color| - puts "#{food} is #{color}" -} - -food_color.each_key { |food| - puts "#{food} is #{food_color[food]}" -} - -# IMO this demonstrates that OO style is by far more readable -food_color.keys.sort.each { |food| - puts "#{food} is #{food_color[food]}." -} - -#----------------------------- -#!/usr/bin/ruby -# countfrom - count number of messages from each sender - -# Default value is 0 -from = Hash.new(0) -while gets - /^From: (.*)/ and from[$1] += 1 -end - -# More useful to sort by number of received mail by person -from.sort {|a,b| b[1]<=>a[1]}.each { |v| - puts "#{v[1]}: #{v[0]}" -} -#----------------------------- - - -# @@PLEAC@@_5.5 -# You may use the built-in 'inspect' method this way: -p hash - -# Or do it the Cookbook way: -hash.each { |k,v| puts "#{k} => #{v}" } - -# Sorted by keys -hash.sort.each { |e| puts "#{e[0]} => #{e[1]}" } -# Sorted by values -hash.sort{|a,b| a[1]<=>b[1]}.each { |e| puts "#{e[0]} => #{e[1]}" } - - -# @@PLEAC@@_5.7 -ttys = Hash.new -for i in `who` - user, tty = i.split - (ttys[user] ||= []) << tty # see problems_ruby for more infos -end -ttys.keys.sort.each { |k| - puts "#{k}: #{commify_series(ttys[k])}" # from 4.2 -} - - -# @@PLEAC@@_5.8 -surname = { "Mickey" => "Mantle", "Babe" => "Ruth" } -puts surname.index("Mantle") - -# If you really needed to 'invert' the whole hash, use Hash#invert - -#----------------------------- -#!/usr/bin/ruby -w -# foodfind - find match for food or color - -given = ARGV.shift or raise "usage: foodfind food_or_color" - -color = { - "Apple" => "red", - "Banana" => "yellow", - "Lemon" => "yellow", - "Carrot" => "orange", -} - -if (color.has_key?(given)) - puts "#{given} is a food with color #{color[given]}." -end -if (color.has_value?(given)) - puts "#{color.index(given)} is a food with color #{given}." -end -#----------------------------- - - -# @@PLEAC@@_5.9 -# Sorted by keys (Hash#sort gives an Array of pairs made of each key,value) -food_color.sort.each { |f| - puts "#{f[0]} is #{f[1]}." -} - -# Sorted by values -food_color.sort { |a,b| a[1] <=> b[1] }.each { |f| - puts "#{f[0]} is #{f[1]}." -} - -# Sorted by length of values -food_color.sort { |a,b| a[1].length <=> b[1].length }.each { |f| - puts "#{f[0]} is #{f[1]}." -} - - -# @@PLEAC@@_5.10 -merged = a.clone.update(b) # because Hash#update changes object in place - -drink_color = { "Galliano" => "yellow", "Mai Tai" => "blue" } -ingested_color = drink_color.clone.update(food_color) - -substance_color = {} -for i in [ food_color, drink_color ] - i.each_key { |k| - if substance_color.has_key?(k) - puts "Warning: #{k} seen twice. Using the first definition." - next - end - substance_color[k] = 1 - } -end - - -# @@PLEAC@@_5.11 -common = hash1.keys & hash2.keys - -this_not_that = hash1.keys - hash2.keys - - -# @@PLEAC@@_5.12 -# no problem here, Ruby handles any kind of object for key-ing -# (it takes Object#hash, which defaults to Object#id) - - -# @@PLEAC@@_5.13 -# AFAIK, not possible in Ruby - - -# @@PLEAC@@_5.14 -# Be careful, the following is possible only because Fixnum objects are -# special (documentation says: there is effectively only one Fixnum object -# instance for any given integer value). -count = Hash.new(0) -array.each { |e| - count[e] += 1 -} - - -# @@PLEAC@@_5.15 -father = { - "Cain" , "Adam", - "Abel" , "Adam", - "Seth" , "Adam", - "Enoch" , "Cain", - "Irad" , "Enoch", - "Mehujael" , "Irad", - "Methusael" , "Mehujael", - "Lamech" , "Methusael", - "Jabal" , "Lamech", - "Jubal" , "Lamech", - "Tubalcain" , "Lamech", - "Enos" , "Seth", -} - -while gets - chomp - begin - print $_, " " - end while $_ = father[$_] - puts -end - -children = {} -father.each { |k,v| - (children[v] ||= []) << k -} -while gets - chomp - puts "#{$_} begat #{(children[$_] || ['Nobody']).join(', ')}.\n" -end - -includes = {} -files.each { |f| - begin - for l in IO.readlines(f) - next unless l =~ /^\s*#\s*include\s*<([^>]+)>/ - (includes[$1] ||= []) << f - end - rescue SystemCallError - $stderr.puts "#$! (skipping)" - end -} - -include_free = includes.values.flatten.uniq - includes.keys - - -# @@PLEAC@@_5.16 -# dutree - print sorted intented rendition of du output -#% dutree -#% dutree /usr -#% dutree -a -#% dutree -a /bin - -# The DuNode class collects all information about a directory, -# and provides some convenience methods -class DuNode - - attr_reader :name - attr_accessor :size - attr_accessor :kids - - def initialize(name) - @name = name - @kids = [] - @size = 0 - end - - # support for sorting nodes with side - def size_compare(node2) - @size <=> node2.size - end - - def basename - @name.sub(/.*\//, "") - end - - #returns substring before last "/", nil if not there - def parent - p = @name.sub(/\/[^\/]+$/,"") - if p == @name - nil - else - p - end - end - -end - -# The DuTree does the acdtual work of -# getting the input, parsing it, builging up a tree -# and format it for output -class Dutree - - attr_reader :topdir - - def initialize - @nodes = Hash.new - @dirsizes = Hash.new(0) - @kids = Hash.new([]) - end - - # get a node by name, create it if it does not exist yet - def get_create_node(name) - if @nodes.has_key?(name) - @nodes[name] - else - node = DuNode.new(name) - @nodes[name] = node - node - end - end - - # run du, read in input, save sizes and kids - # stores last directory read in instance variable topdir - def input(arguments) - name = "" - cmd = "du " + arguments.join(" ") - IO.popen(cmd) { |pipe| - pipe.each { |line| - size, name = line.chomp.split(/\s+/, 2) - node = get_create_node(name) - node.size = size.to_i - @nodes[name] = node - parent = node.parent - if parent - get_create_node(parent).kids.push(node) - end - } - } - @topdir = @nodes[name] - end - - # figure out how much is taken in each directory - # that isn't stored in the subdirectories. Add a new - # fake kid called "." containing that much. - def get_dots(node) - cursize = node.size - for kid in node.kids - cursize -= kid.size - get_dots(kid) - end - if node.size != cursize - newnode = get_create_node(node.name + "/.") - newnode.size = cursize - node.kids.push(newnode) - end - end - - # recursively output everything - # passing padding and number width as well - # on recursive calls - def output(node, prefix="", width=0) - line = sprintf("%#{width}d %s", node.size, node.basename) - puts(prefix + line) - prefix += line.sub(/\d /, "| ") - prefix.gsub!(/[^|]/, " ") - if node.kids.length > 0 # not a bachelor node - kids = node.kids - kids.sort! { |a,b| - b.size_compare(a) - } - width = kids[0].size.to_s.length - for kid in kids - output(kid, prefix, width) - end - end - end - -end - -tree = Dutree.new -tree.input(ARGV) -tree.get_dots(tree.topdir) -tree.output(tree.topdir) - - -# @@PLEAC@@_6.0 -# The verbose version are match, sub, gsub, sub! and gsub!; -# pattern needs to be a Regexp object; it yields a MatchData -# object. -pattern.match(string) -string.sub(pattern, replacement) -string.gsub(pattern, replacement) -# As usual in Ruby, sub! does the same as sub but also modifies -# the object, the same for gsub!/gsub. - -# Sugared syntax yields the position of the match (or nil if no -# match). Note that the object at the right of the operator needs -# not to be a Regexp object (it can be a String). The "dont -# match" operator yields true or false. -meadow =~ /sheep/ # position of the match, nil if no match -meadow !~ /sheep/ # true if doesn't match, false if it does -# There is no sugared version for the substitution - -meadow =~ /\bovines?\b/i and print "Here be sheep!" - -string = "good food" -string.sub!(/o*/, 'e') - -# % echo ababacaca | ruby -ne 'puts $& if /(a|ba|b)+(a|ac)+/' -# ababa - -# The "global" (or "multiple") match is handled by String#scan -scan (/(\d+)/) { - puts "Found number #{$1}" -} - -# String#scan yields an Array if not used with a block -numbers = scan(/\d+/) - -digits = "123456789" -nonlap = digits.scan(/(\d\d\d)/) -yeslap = digits.scan(/(?=(\d\d\d))/) -puts "Non-overlapping: #{nonlap.join(' ')}" -puts "Overlapping: #{yeslap.join(' ')}"; -# Non-overlapping: 123 456 789 -# Overlapping: 123 234 345 456 567 678 789 - -string = "And little lambs eat ivy" -string =~ /l[^s]*s/ -puts "(#$`) (#$&) (#$')" -# (And ) (little lambs) ( eat ivy) - - -# @@PLEAC@@_6.1 -# Ruby doesn't have the same problem: -dst = src.sub('this', 'that') - -progname = $0.sub('^.*/', '') - -bindirs = %w(/usr/bin /bin /usr/local/bin) -libdirs = bindirs.map { |l| l.sub('bin', 'lib') } - - -# @@PLEAC@@_6.3 -/\S+/ # as many non-whitespace bytes as possible -/[A-Za-z'-]+/ # as many letters, apostrophes, and hyphens - -/\b([A-Za-z]+)\b/ # usually best -/\s([A-Za-z]+)\s/ # fails at ends or w/ punctuation - - -# @@PLEAC@@_6.4 -require 'socket' -str = 'www.ruby-lang.org and www.rubygarden.org' -re = / - ( # capture the hostname in $1 - (?: # these parens for grouping only - (?! [-_] ) # lookahead for neither underscore nor dash - [\w-] + # hostname component - \. # and the domain dot - ) + # now repeat that whole thing a bunch of times - [A-Za-z] # next must be a letter - [\w-] + # now trailing domain part - ) # end of $1 capture - /x # /x for nice formatting - -str.gsub! re do # pass a block to execute replacement - host = TCPsocket.gethostbyname($1) - "#{$1} [#{host[3]}]" -end - -puts str -#----------------------------- -# to match whitespace or #-characters in an extended re you need to escape -# them. - -foo = 42 -str = 'blah #foo# blah' -str.gsub! %r/ # replace - \# # a pound sign - (\w+) # the variable name - \# # another pound sign - /x do - eval $1 # with the value of a local variable - end -puts str # => blah 42 blah - - -# @@PLEAC@@_6.5 -# The 'g' modifier doesn't exist in Ruby, a regexp can't be used -# directly in a while loop; instead, use String#scan { |match| .. } -fish = 'One fish two fish red fish blue fish' -WANT = 3 -count = 0 -fish.scan(/(\w+)\s+fish\b/i) { - if (count += 1) == WANT - puts "The third fish is a #{$1} one." - end -} - -if fish =~ /(?:\w+\s+fish\s+){2}(\w+)\s+fish/i - puts "The third fish is a #{$1} one." -end - -pond = 'One fish two fish red fish blue fish' -# String#scan without a block gives an array of matches, each match -# being an array of all the specified groups -colors = pond.scan(/(\w+)\s+fish\b/i).flatten # get all matches -color = colors[2] # then the one we want -# or without a temporary array -color = pond.scan(/(\w+)\s+fish\b/i).flatten[2] # just grab element 3 -puts "The third fish in the pond is #{color}." - -count = 0 -fishes = 'One fish two fish red fish blue fish' -evens = fishes.scan(/(\w+)\s+fish\b/i).select { (count+=1) % 2 == 0 } -print "Even numbered fish are #{evens.join(' ')}." - -count = 0 -fishes.gsub(/ - \b # makes next \w more efficient - ( \w+ ) # this is what we\'ll be changing - ( - \s+ fish \b - ) - /x) { - if (count += 1) == 4 - 'sushi' + $2 - else - $1 + $2 - end -} - -pond = 'One fish two fish red fish blue fish swim here.' -puts "Last fish is #{pond.scan(/\b(\w+)\s+fish\b/i).flatten[-1]}" - -/ - A # find some pattern A - (?! # mustn\'t be able to find - .* # something - A # and A - ) - $ # through the end of the string -/x - -# The "s" perl modifier is "m" in Ruby (not very nice since there is -# also an "m" in perl..) -pond = "One fish two fish red fish blue fish swim here." -if (pond =~ / - \b ( \w+) \s+ fish \b - (?! .* \b fish \b ) - /mix) - puts "Last fish is #{$1}." -else - puts "Failed!" -end - - -# @@PLEAC@@_6.6 -#----------------------------- -#!/usr/bin/ruby -w -# killtags - very bad html killer -$/ = nil; # each read is whole file -while file = gets() do - file.gsub!(/<.*?>/m,''); # strip tags (terribly) - puts file # print file to STDOUT -end -#----------------------------- -#!/usr/bin/ruby -w -#headerfy - change certain chapter headers to html -$/ = '' -while file = gets() do - pattern = / - \A # start of record - ( # capture in $1 - Chapter # text string - \s+ # mandatory whitespace - \d+ # decimal number - \s* # optional whitespace - : # a real colon - . * # anything not a newline till end of line - ) - /x - puts file.gsub(pattern,'<H1>\1</H1>') -end -#----------------------------- -#% ruby -00pe "gsub!(/\A(Chapter\s+\d+\s*:.*)/,'<H1>\1</H1>')" datafile - -#!/usr/bin/ruby -w -#----------------------------- -for file in ARGV - file = File.open(ARGV.shift) - while file.gets('') do # each read is a paragraph - print "chunk #{$.} in $ARGV has <<#{$1}>>\n" while /^START(.*?)^END/m - end # /m activates the multiline mode -end -#----------------------------- - -# @@PLEAC@@_6.7 -#----------------------------- -$/ = nil; -file = File.open("datafile") -chunks = file.gets.split(/pattern/) -#----------------------------- -# .Ch, .Se and .Ss divide chunks of STDIN -chunks = gets(nil).split(/^\.(Ch|Se|Ss)$/) -print "I read #{chunks.size} chunks.\n" -#----------------------------- - - -# @@PLEAC@@_6.8 -while gets - if ~/BEGIN/ .. ~/END/ - # line falls between BEGIN and END inclusive - end -end - -while gets - if ($. == firstnum) .. ($. == lastnum) - # operate between firstnum and lastnum line number - end -end - -# in ruby versions prior to 1.8, the above two conditional -# expressions could be shortened to: -# if /BEGIN/ .. /END/ -# and -# if firstnum .. lastnum -# but these now only work this way from the command line - -#----------------------------- - -while gets - if ~/BEGIN/ ... ~/END/ - # line falls between BEGIN and END on different lines - end -end - -while gets - if ($. == first) ... ($. == last) - # operate between first and last line number on different lines - end -end - -#----------------------------- -# command-line to print lines 15 through 17 inclusive (see below) -ruby -ne 'print if 15 .. 17' datafile - -# print out all <XMP> .. </XMP> displays from HTML doc -while gets - print if ~%r#<XMP>#i .. ~%r#</XMP>#i; -end - -# same, but as shell command -# ruby -ne 'print if %r#<XMP>#i .. %r#</XMP>#i' document.html -#----------------------------- -# ruby -ne 'BEGIN { $top=3; $bottom=5 }; \ -# print if $top .. $bottom' /etc/passwd # FAILS -# ruby -ne 'BEGIN { $top=3; $bottom=5 }; \ -# print if $. == $top .. $. == $bottom' /etc/passwd # works -# ruby -ne 'print if 3 .. 5' /etc/passwd # also works -#----------------------------- -print if ~/begin/ .. ~/end/; -print if ~/begin/ ... ~/end/; -#----------------------------- -while gets - $in_header = $. == 1 .. ~/^$/ ? true : false - $in_body = ~/^$/ .. ARGF.eof ? true : false -end -#----------------------------- -seen = {} -ARGF.each do |line| - next unless line =~ /^From:?\s/i .. line =~ /^$/; - line.scan(%r/([^<>(),;\s]+\@[^<>(),;\s]+)/).each do |addr| - puts addr unless seen[addr] - seen[addr] ||= 1 - end -end - - -# @@PLEAC@@_6.9 -def glob2pat(globstr) - patmap = { - '*' => '.*', - '?' => '.', - '[' => '[', - ']' => ']', - } - globstr.gsub!(/(.)/) { |c| patmap[c] || Regexp::escape(c) } - '^' + globstr + '$' -end - - -# @@PLEAC@@_6.10 -# avoid interpolating patterns like this if the pattern -# isn't going to change: -pattern = ARGV.shift -ARGF.each do |line| - print line if line =~ /#{pattern}/ -end - -# the above creates a new regex each iteration. Instead, -# use the /o modifier so the regex is compiled only once - -pattern = ARGV.shift -ARGF.each do |line| - print line if line =~ /#{pattern}/o -end - -#----------------------------- - -#!/usr/bin/ruby -# popgrep1 - grep for abbreviations of places that say "pop" -# version 1: slow but obvious way -popstates = %w(CO ON MI WI MN) -ARGF.each do |line| - popstates.each do |state| - if line =~ /\b#{state}\b/ - print line - last - end - end -end - -#----------------------------- -#!/usr/bin/ruby -# popgrep2 - grep for abbreviations of places that say "pop" -# version 2: eval strings; fast but hard to quote -popstates = %w(CO ON MI WI MN) -code = "ARGF.each do |line|\n" -popstates.each do |state| - code += "\tif line =~ /\\b#{state}\\b/; print(line); next; end\n" -end -code += "end\n" -print "CODE IS\n---\n#{code}\n---\n" if false # turn on for debugging -eval code - -# CODE IS -# --- -# ARGF.each do |line| -# if line =~ /\bCO\b/; print(line); next; end -# if line =~ /\bON\b/; print(line); next; end -# if line =~ /\bMI\b/; print(line); next; end -# if line =~ /\bWI\b/; print(line); next; end -# if line =~ /\bMN\b/; print(line); next; end -# end -# -# --- - -## alternatively, the same idea as above but compiling -## to a case statement: (not in perlcookbook) -#!/usr/bin/ruby -w -# popgrep2.5 - grep for abbreviations of places that say "pop" -# version 2.5: eval strings; fast but hard to quote -popstates = %w(CO ON MI WI MN) -code = "ARGF.each do |line|\n case line\n" -popstates.each do |state| - code += " when /\\b#{state}\\b/ : print line\n" -end -code += " end\nend\n" -print "CODE IS\n---\n#{code}\n---\n" if false # turn on for debugging -eval code - -# CODE IS -# --- -# ARGF.each do |line| -# case line -# when /\bCO\b/ : print line -# when /\bON\b/ : print line -# when /\bMI\b/ : print line -# when /\bWI\b/ : print line -# when /\bMN\b/ : print line -# end -# end -# -# --- - -# Note: (above) Ruby 1.8+ allows the 'when EXP : EXPR' on one line -# with the colon separator. - -#----------------------------- -#!/usr/bin/ruby -# popgrep3 - grep for abbreviations of places that say "pop" -# version3: build a match_any function -popstates = %w(CO ON MI WI MN) -expr = popstates.map{|e|"line =~ /\\b#{e}\\b/"}.join('||') -eval "def match_any(line); #{expr};end" -ARGF.each do |line| - print line if match_any(line) -end -#----------------------------- - -## building a match_all function is a trivial -## substitution of && for || -## here is a generalized example: -#!/usr/bin/ruby -w -## grepauth - print lines that mention both foo and bar -class MultiMatch - def initialize(*patterns) - _any = build_match('||',patterns) - _all = build_match('&&',patterns) - eval "def match_any(line);#{_any};end\n" - eval "def match_all(line);#{_all};end\n" - end - def build_match(sym,args) - args.map{|e|"line =~ /#{e}/"}.join(sym) - end -end - -mm = MultiMatch.new('foo','bar') -ARGF.each do |line| - print line if mm.match_all(line) -end -#----------------------------- - -#!/usr/bin/ruby -# popgrep4 - grep for abbreviations of places that say "pop" -# version4: pretty fast, but simple: compile all re's first: -popstates = %w(CO ON MI WI MN) -popstates = popstates.map{|re| %r/\b#{re}\b/} -ARGF.each do |line| - popstates.each do |state_re| - if line =~ state_re - print line - break - end - end -end - -## speeds trials on the jargon file(412): 26006 lines, 1.3MB -## popgrep1 => 7.040s -## popgrep2 => 0.656s -## popgrep2.5 => 0.633s -## popgrep3 => 0.675s -## popgrep4 => 1.027s - -# unless speed is criticial, the technique in popgrep4 is a -# reasonable balance between speed and logical simplicity. - - -# @@PLEAC@@_6.11 -begin - print "Pattern? " - pat = $stdin.gets.chomp - Regexp.new(pat) -rescue - warn "Invalid Pattern" - retry -end - - -# @@PLEAC@@_6.13 -# uses the 'amatch' extension found on: -# http://raa.ruby-lang.org/project/amatch/ -require 'amatch' -matcher = Amatch.new('balast') -#$relative, $distance = 0, 1 -File.open('/usr/share/dict/words').each_line do |line| - print line if matcher.search(line) <= 1 -end -__END__ -#CODE -ballast -ballasts -balustrade -balustrades -blast -blasted -blaster -blasters -blasting -blasts - - -# @@PLEAC@@_6.14 -str.scan(/\G(\d)/).each do |token| - puts "found #{token}" -end -#----------------------------- -n = " 49 here" -n.gsub!(/\G /,'0') -puts n -#----------------------------- -str = "3,4,5,9,120" -str.scan(/\G,?(\d+)/).each do |num| - puts "Found number: #{num}" -end -#----------------------------- -# Ruby doesn't have the String.pos or a /c re modifier like Perl -# But it does have StringScanner in the standard library (strscn) -# which allows similar functionality: - -require 'strscan' -text = 'the year 1752 lost 10 days on the 3rd of September' -sc = StringScanner.new(text) -while sc.scan(/.*?(\d+)/) - print "found: #{sc[1]}\n" -end -if sc.scan(/\S+/) - puts "Found #{sc[0]} after last number" -end -#----------------------------- -# assuming continuing from above: -puts "The position in 'text' is: #{sc.pos}" -sc.pos = 30 -puts "The position in 'text' is: #{sc.pos}" - - -# @@PLEAC@@_6.15 -#----------------------------- -# greedy pattern -str.gsub!(/<.*>/m,'') # not good - -# non-greedy (minimal) pattern -str.gsub!(/<.*?>/m,'') # not great - - -#----------------------------- -#<b><i>this</i> and <i>that</i> are important</b> Oh, <b><i>me too!</i></b> -#----------------------------- -%r{ <b><i>(.*?)</i></b> }mx -#----------------------------- -%r/BEGIN((?:(?!BEGIN).)*)END/ -#----------------------------- -%r{ <b><i>( (?: (?!</b>|</i>). )* ) </i></b> }mx -#----------------------------- -%r{ <b><i>( (?: (?!</[ib]>). )* ) </i></b> }mx -#----------------------------- -%r{ - <b><i> - [^<]* # stuff not possibly bad, and not possibly the end. - (?: - # at this point, we can have '<' if not part of something bad - (?! </?[ib]> ) # what we can't have - < # okay, so match the '<' - [^<]* # and continue with more safe stuff - ) * - </i></b> - }mx - - -# @@PLEAC@@_6.16 -#----------------------------- -$/ = "" -ARGF.each do |para| - para.scan %r/ - \b # start at word boundary - (\S+) # find chunk of non-whitespace - \b # until a word boundary - ( - \s+ # followed by whitespace - \1 # and that same chunk again - \b # and a word boundary - ) + # one or more times - /xi do - puts "dup word '#{$1}' at paragraph #{$.}" - end -end -#----------------------------- -astr = 'nobody' -bstr = 'bodysnatcher' -if "#{astr} #{bstr}" =~ /^(\w+)(\w+) \2(\w+)$/ - print "#{$2} overlaps in #{$1}-#{$2}-#{$3}" -end -#----------------------------- -#!/usr/bin/ruby -w -# prime_pattern -- find prime factors of argument using patterns -ARGV << 180 -cap = 'o' * ARGV.shift -while cap =~ /^(oo+?)\1+$/ - print $1.size, " " - cap.gsub!(/#{$1}/,'o') -end -puts cap.size -#----------------------------- -#diophantine -# solve for 12x + 15y + 16z = 281, maximizing x -if ('o' * 281).match(/^(o*)\1{11}(o*)\2{14}(o*)\3{15}$/) - x, y, z = $1.size, $2.size, $3.size - puts "One solution is: x=#{x}; y=#{y}; z=#{z}" -else - puts "No solution." -end -# => One solution is: x=17; y=3; z=2 - -#----------------------------- -# using different quantifiers: -('o' * 281).match(/^(o+)\1{11}(o+)\2{14}(o+)\3{15}$/) -# => One solution is: x=17; y=3; z=2 - -('o' * 281).match(/^(o*?)\1{11}(o*)\2{14}(o*)\3{15}$/) -# => One solution is: x=0; y=7; z=11 - -('o' * 281).match(/^(o+?)\1{11}(o*)\2{14}(o*)\3{15}$/) -# => One solution is: x=1; y=3; z=14 - - -# @@PLEAC@@_6.17 -# alpha OR beta -%r/alpha|beta/ - -# alpha AND beta -%r/(?=.*alpha)(?=.*beta)/m - -# alpha AND beta, no overlap -%r/alpha.*beta|beta.*alpha/m - -# NOT beta -%r/^(?:(?!beta).)*$/m - -# NOT bad BUT good -%r/(?=(?:(?!BAD).)*$)GOOD/m -#----------------------------- - -if !(string =~ /pattern/) # ugly - something() -end - -if string !~ /pattern/ # preferred - something() -end - - -#----------------------------- -if string =~ /pat1/ && string =~ /pat2/ - something() -end -#----------------------------- -if string =~ /pat1/ || string =~ /pat2/ - something() -end -#----------------------------- -#!/usr/bin/ruby -w -# minigrep - trivial grep -pat = ARGV.shift -ARGF.each do |line| - print line if line =~ /#{pat}/o -end -#----------------------------- - "labelled" =~ /^(?=.*bell)(?=.*lab)/m -#----------------------------- -$string =~ /bell/ && $string =~ /lab/ -#----------------------------- -$murray_hill = "blah bell blah " -if $murray_hill =~ %r{ - ^ # start of string - (?= # zero-width lookahead - .* # any amount of intervening stuff - bell # the desired bell string - ) # rewind, since we were only looking - (?= # and do the same thing - .* # any amount of intervening stuff - lab # and the lab part - ) - }mx # /m means . can match newline - - print "Looks like Bell Labs might be in Murray Hill!\n"; -end -#----------------------------- -"labelled" =~ /(?:^.*bell.*lab)|(?:^.*lab.*bell)/ -#----------------------------- -$brand = "labelled"; -if $brand =~ %r{ - (?: # non-capturing grouper - ^ .*? # any amount of stuff at the front - bell # look for a bell - .*? # followed by any amount of anything - lab # look for a lab - ) # end grouper - | # otherwise, try the other direction - (?: # non-capturing grouper - ^ .*? # any amount of stuff at the front - lab # look for a lab - .*? # followed by any amount of anything - bell # followed by a bell - ) # end grouper - }mx # /m means . can match newline - print "Our brand has bell and lab separate.\n"; -end -#----------------------------- -$map =~ /^(?:(?!waldo).)*$/s -#----------------------------- -$map = "the great baldo" -if $map =~ %r{ - ^ # start of string - (?: # non-capturing grouper - (?! # look ahead negation - waldo # is he ahead of us now? - ) # is so, the negation failed - . # any character (cuzza /s) - ) * # repeat that grouping 0 or more - $ # through the end of the string - }mx # /m means . can match newline - print "There's no waldo here!\n"; -end -=begin - 7:15am up 206 days, 13:30, 4 users, load average: 1.04, 1.07, 1.04 - -USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT - -tchrist tty1 5:16pm 36days 24:43 0.03s xinit - -tchrist tty2 5:19pm 6days 0.43s 0.43s -tcsh - -tchrist ttyp0 chthon 7:58am 3days 23.44s 0.44s -tcsh - -gnat ttyS4 coprolith 2:01pm 13:36m 0.30s 0.30s -tcsh -=end -#% w | minigrep '^(?!.*ttyp).*tchrist' -#----------------------------- -%r{ - ^ # anchored to the start - (?! # zero-width look-ahead assertion - .* # any amount of anything (faster than .*?) - ttyp # the string you don't want to find - ) # end look-ahead negation; rewind to start - .* # any amount of anything (faster than .*?) - tchrist # now try to find Tom -}x -#----------------------------- -#% w | grep tchrist | grep -v ttyp -#----------------------------- -#% grep -i 'pattern' files -#% minigrep '(?i)pattern' files -#----------------------------- - - -# @@PLEAC@@_6.20 -ans = $stdin.gets.chomp -re = %r/^#{Regexp.quote(ans)}/ -case - when "SEND" =~ re : puts "Action is send" - when "STOP" =~ re : puts "Action is stop" - when "ABORT" =~ re : puts "Action is abort" - when "EDIT" =~ re : puts "Action is edit" -end -#----------------------------- -require 'abbrev' -table = Abbrev.abbrev %w-send stop abort edit- -loop do - print "Action: " - ans = $stdin.gets.chomp - puts "Action for #{ans} is #{table[ans.downcase]}" -end - - -#----------------------------- -# dummy values are defined for 'file', 'PAGER', and -# the 'invoke_editor' and 'deliver_message' methods -# do not do anything interesting in this example. -#!/usr/bin/ruby -w -require 'abbrev' - -file = 'pleac_ruby.data' -PAGER = 'less' - -def invoke_editor - puts "invoking editor" -end - -def deliver_message - puts "delivering message" -end - -actions = { - 'edit' => self.method(:invoke_editor), - 'send' => self.method(:deliver_message), - 'list' => proc {system(PAGER, file)}, - 'abort' => proc {puts "See ya!"; exit}, - "" => proc {puts "Unknown Command"} -} - -dtable = Abbrev.abbrev(actions.keys) -loop do - print "Action: " - ans = $stdin.gets.chomp.delete(" \t") - actions[ dtable[ans.downcase] || "" ].call -end - - -# @@PLEAC@@_6.19 -#----------------------------- -# basically, the Perl Cookbook categorizes this as an -# unsolvable problem ... -#----------------------------- -1 while addr.gsub!(/\([^()]*\)/,'') -#----------------------------- -Dear someuser@host.com, - -Please confirm the mail address you gave us Wed May 6 09:38:41 -MDT 1998 by replying to this message. Include the string -"Rumpelstiltskin" in that reply, but spelled in reverse; that is, -start with "Nik...". Once this is done, your confirmed address will -be entered into our records. - - -# @@PLEAC@@_6.21 -#----------------------------- -#% gunzip -c ~/mail/archive.gz | urlify > archive.urlified -#----------------------------- -#% urlify ~/mail/*.inbox > ~/allmail.urlified -#----------------------------- -#!/usr/bin/ruby -w -# urlify - wrap HTML links around URL-like constructs - -urls = '(https?|telnet|gopher|file|wais|ftp)'; -ltrs = '\w'; -gunk = '/#~:.?+=&%@!\-'; -punc = '.:?\-'; -any = "#{ltrs}#{gunk}#{punc}"; - -ARGF.each do |line| - line.gsub! %r/ - \b # start at word boundary - ( # begin $1 { - #{urls} : # need resource and a colon - [#{any}] +? # followed by on or more - # of any valid character, but - # be conservative and take only - # what you need to.... - ) # end $1 } - (?= # look-ahead non-consumptive assertion - [#{punc}]* # either 0 or more punctuation - [^#{any}] # followed by a non-url char - | # or else - $ # then end of the string - ) - /iox do - %Q|<A HREF="#{$1}">#{$1}</A>| - end - print line -end - - -# @@PLEAC@@_6.23 -%r/^m*(d?c{0,3}|c[dm])(l?x{0,3}|x[lc])(v?i{0,3}|i[vx])$/i -#----------------------------- -str.sub!(/(\S+)(\s+)(\S+)/, '\3\2\1') -#----------------------------- -%r/(\w+)\s*=\s*(.*)\s*$/ # keyword is $1, value is $2 -#----------------------------- -%r/.{80,}/ -#----------------------------- -%r|(\d+)/(\d+)/(\d+) (\d+):(\d+):(\d+)| -#----------------------------- -str.gsub!(%r|/usr/bin|,'/usr/local/bin') -#----------------------------- -str.gsub!(/%([0-9A-Fa-f][0-9A-Fa-f])/){ $1.hex.chr } -#----------------------------- -str.gsub!(%r{ - /\* # Match the opening delimiter - .*? # Match a minimal number of characters - \*/ # Match the closing delimiter -}xm,'') -#----------------------------- -str.sub!(/^\s+/, '') -str.sub!(/\s+$/, '') - -# but really, in Ruby we'd just do: -str.strip! -#----------------------------- -str.gsub!(/\\n/,"\n") -#----------------------------- -str.sub!(/^.*::/, '') -#----------------------------- -%r/^([01]?\d\d|2[0-4]\d|25[0-5])\.([01]?\d\d|2[0-4]\d|25[0-5])\. - ([01]?\d\d|2[0-4]\d|25[0-5])\.([01]?\d\d|2[0-4]\d|25[0-5])$/x -#----------------------------- -str.sub!(%r|^.*/|, '') -#----------------------------- -cols = ( (ENV['TERMCAP'] || " ") =~ /:co#(\d+):/ ) ? $1 : 80; -#----------------------------- -name = " #{$0} #{ARGV}".gsub(%r| /\S+/|, ' ') -#----------------------------- -require 'rbconfig' -include Config -raise "This isn't Linux" unless CONFIG['target_os'] =~ /linux/i; -#----------------------------- -str.gsub!(%r/\n\s+/, ' ') -#----------------------------- -nums = str.scan(/(\d+\.?\d*|\.\d+)/) -#----------------------------- -capwords = str.scan(%r/(\b[^\Wa-z0-9_]+\b)/) -#----------------------------- -lowords = str.scan(%r/(\b[^\WA-Z0-9_]+\b)/) -#----------------------------- -icwords = str.scan(%r/(\b[^\Wa-z0-9_][^\WA-Z0-9_]*\b)/) -#----------------------------- -links = str.scan(%r/<A[^>]+?HREF\s*=\s*["']?([^'" >]+?)[ '"]?>/mi) -#----------------------------- -initial = str =~ /^\S+\s+(\S)\S*\s+\S/ ? $1 : "" -#----------------------------- -str.gsub!(%r/"([^"]*)"/, %q-``\1''-) -#----------------------------- - -$/ = "" -sentences = [] -ARGF.each do |para| - para.gsub!(/\n/, ' ') - para.gsub!(/ {3,}/,' ') - sentences << para.scan(/(\S.*?[!?.])(?= |\Z)/) -end - -#----------------------------- -%r/(\d{4})-(\d\d)-(\d\d)/ # YYYY in $1, MM in $2, DD in $3 -#----------------------------- -%r/ ^ - (?: - 1 \s (?: \d\d\d \s)? # 1, or 1 and area code - | # ... or ... - \(\d\d\d\) \s # area code with parens - | # ... or ... - (?: \+\d\d?\d? \s)? # optional +country code - \d\d\d ([\s\-]) # and area code - ) - \d\d\d (\s|\1) # prefix (and area code separator) - \d\d\d\d # exchange - $ - /x -#----------------------------- -%r/\boh\s+my\s+gh?o(d(dess(es)?|s?)|odness|sh)\b/i -#----------------------------- -lines = [] -lines << $1 while input.sub!(/^([^\012\015]*)(\012\015?|\015\012?)/,'') - - -# @@PLEAC@@_7.0 -# An IO object being Enumerable, we can use 'each' directly on it -File.open("/usr/local/widgets/data").each { |line| - puts line if line =~ /blue/ -} - -logfile = File.new("/var/log/rubylog.txt", "w") -mysub($stdin, logfile) - -# The method IO#readline is similar to IO#gets -# but throws an exception when it reaches EOF -f = File.new("bla.txt") -begin - while (line = f.readline) - line.chomp - $stdout.print line if line =~ /blue/ - end -rescue EOFError - f.close -end - -while $stdin.gets # reads from STDIN - unless (/\d/) - $stderr.puts "No digit found." # writes to STDERR - end - puts "Read: #{$_}" # writes to STDOUT -end - -logfile = File.new("/tmp/log", "w") - -logfile.close - -# $defout (or its synonym '$>') is the destination of output -# for Kernel#print, Kernel#puts, and family functions -logfile = File.new("log.txt", "w") -old = $defout -$defout = logfile # switch to logfile for output -puts "Countdown initiated ..." -$defout = old # return to original output -puts "You have 30 seconds to reach minimum safety distance." - - -# @@PLEAC@@_7.1 -source = File.new(path, "r") # open file "path" for reading only -sink = File.new(path, "w") # open file "path" for writing only - -source = File.open(path, File::RDONLY) # open file "path" for reading only -sink = File.open(path, File::WRONLY) # open file "path" for writing only - -file = File.open(path, "r+") # open "path" for reading and writing -file = File.open(path, flags) # open "path" with the flags "flags" (see examples below for flags) - -# open file "path" read only -file = File.open(path, "r") -file = File.open(path, File::RDONLY) - -# open file "path" write only, create it if it does not exist -# truncate it to zero length if it exists -file = File.open(path, "w") -file = File.open(path, File::WRONLY|File::TRUNC|File::CREAT) -file = File.open(path, File::WRONLY|File::TRUNC|File::CREAT, 0666) # with permission 0666 - -# open file "path" write only, fails if file exists -file = File.open(path, File::WRONLY|File::EXCL|File::CREAT) -file = File.open(path, File::WRONLY|File::EXCL|File::CREAT, 0666) - -# open file "path" for appending -file = File.open(path, "a") -file = File.open(path, File::WRONLY|File::APPEND|File::CREAT) -file = File.open(path, File::WRONLY|File::APPEND|File::CREAT, 0666) - -# open file "path" for appending only when file exists -file = File.open(path, File::WRONLY|File::APPEND) - -# open file "path" for reading and writing -file = File.open(path, "r+") -file = File.open(path, File::RDWR) - -# open file for reading and writing, create a new file if it does not exist -file = File.open(path, File::RDWR|File::CREAT) -file = File.open(path, File::RDWR|File::CREAT, 0600) - -# open file "path" reading and writing, fails if file exists -file = File.open(path, File::RDWR|File::EXCL|File::CREAT) -file = File.open(path, File::RDWR|File::EXCL|File::CREAT, 0600) - - -# @@PLEAC@@_7.2 -# No problem with Ruby since the filename doesn't contain characters with -# special meaning; like Perl's sysopen -File.open(filename, 'r') - - -# @@PLEAC@@_7.3 -File.expand_path('~root/tmp') -#=> "/root/tmp" -File.expand_path('~rpcuser') -#=> "/var/lib/nfs" - -# To expand ~/.. it explicitely needs the environment variable HOME -File.expand_path('~/tmp') -#=> "/home/gc/tmp" - - -# @@PLEAC@@_7.4 -# The exception raised in Ruby reports the filename -File.open('afile') - - -# @@PLEAC@@_7.5 -# Standard Ruby distribution provides the following useful extension -require 'tempfile' -# With the Tempfile class, the file is automatically deleted on garbage -# collection, so you won't need to remove it, later on. -tf = Tempfile.new('tmp') # a name is required to create the filename - -# If you need to pass the filename to an external program you can use -# File#path, but don't forget to File#flush in order to flush anything -# living in some buffer somewhere. -tf.flush -system("/usr/bin/dowhatever #{tf.path}") - -fh = Tempfile.new('tmp') -fh.sync = true # autoflushes -10.times { |i| fh.puts i } -fh.rewind -puts 'Tmp file has: ', fh.readlines - - -# @@PLEAC@@_7.6 -while (DATA.gets) do - # process the line -end -__END__ -# your data goes here -# __DATA__ doesn't exist in Ruby - -#CODE -# get info about the script (size, date of last modification) -kilosize = DATA.stat.size / 1024 -last_modif = DATA.stat.mtime -puts "<P>Script size is #{kilosize}" -puts "<P>Last script update: #{last_modif}" -__END__ -# DO NOT REMOVE THE PRECEEDING LINE. -# Everything else in this file will be ignored. -#CODE - - -# @@PLEAC@@_7.7 -while line = gets do - # do something with line. -end - -# or -while gets do - # do something with $_ -end - -# or more rubyish -$stdin.each do |line| - # do stuff with line -end - - -# ARGF may makes this more easy -# this is skipped if ARGV.size==0 -ARGV.each do |filename| - # closing and exception handling are done by the block - open(filename) do |fd| - fd.each do |line| - # do stuff with line - end - end rescue abort("can't open %s" % filename) -end - -# globbing is done in the Dir module -ARGV = Dir["*.[Cch]"] if ARGV.empty? - -# note: optparse is the preferred way to handle this -if (ARGV[0] == '-c') - chop_first += 1 - ARGV.shift -end - - -# processing numerical options -if ARGV[0] =~ /^-(\d+)$/ - columns = $1 - ARGV.shift -end - -# again, better to use optparse: -require 'optparse' -nostdout = 0 -append = 0 -unbuffer = 0 -ignore_ints = 0 -ARGV.options do |opt| - opt.on('-n') { nostdout +=1 } - opt.on('-a') { append +=1 } - opt.on('-u') { unbuffer +=1 } - opt.on('-i') { ignore_ints +=1 } - opt.parse! -end or abort("usage: " + __FILE__ + " [-ainu] [filenames]") - -# no need to do undef $/, we have File.read -str = File.read(ARGV[0]) - -# again we have File.read -str = File.read(ARGV[0]) - -# not sure what this should do: -# I believe open the file, print filename, lineno and line: -ARGF.each_with_index do |line, idx| - print ARGF.filename, ":", idx, ";", line -end - -# print all the lines in every file passed via command line that contains login -ARGF.each do |line| - puts line if line =~ /login/ -end -# -# even this would fit -#%ruby -ne "print if /f/" 2.log -# - -ARGF.each { |l| puts l.downcase! } - -#------------------ -#!/usr/bin/ruby -p -# just like perl's -p -$_.downcase! -# - -# I don't know who should I trust. -# perl's version splits on \w+ while python's on \w. - -chunks = 0 - -File.read(ARGV[0]).split.each do |word| - next if word =~ /^#/ - break if ["__DATA__", "__END__"].member? word - chunks += 1 -end - -print "Found ", chunks, " chunks\n" - - -# @@PLEAC@@_7.8 -old = File.open(old_file) -new = File.open(new_file, "w") -while old.gets do - # change $_, then... - new.print $_ -end -old.close -new.close -File.rename(old_file, "old.orig") -File.rename(new_file, old_file) - -while old.gets do - if $. == 20 then # we are at the 20th line - new.puts "Extra line 1" - new.puts "Extra line 2" - end - new.print $_ -end - -while old.gets do - next if 20..30 # skip the 20th line to the 30th - # Ruby (and Perl) permit to write if 20..30 - # instead of if (20 <= $.) and ($. <= 30) - new.print $_ -end - - -# @@PLEAC@@_7.9 -#% ruby -i.orig -pe 'FILTER COMMAND' file1 file2 file3 ... -# -#----------------------------- -##!/usr/bin/ruby -i.orig -p -# filter commands go here -#----------------------------- - -#% ruby -pi.orig -e 'gsub!(/DATE/){Time.now)' - -# effectively becomes: -ARGV << 'I' -oldfile = "" -while gets - if ARGF.filename != oldfile - newfile = ARGF.filename - File.rename(newfile, newfile + ".orig") - $stdout = File.open(newfile,'w') - oldfile = newfile - end - gsub!(/DATE/){Time.now} - print -end -$stdout = STDOUT -#----------------------------- -#% ruby -i.old -pe 'gsub!(%r{\bhisvar\b}, 'hervar')' *.[Cchy] - -#----------------------------- -# set up to iterate over the *.c files in the current directory, -# editing in place and saving the old file with a .orig extension -$-i = '.orig' # set up -i mode -ARGV.replace(Dir['*.[Cchy]']) -while gets - if $. == 1 - print "This line should appear at the top of each file\n" - end - gsub!(/\b(p)earl\b/i, '\1erl') # Correct typos, preserving case - print - ARGF.close if ARGF.eof -end - - -# @@PLEAC@@_7.10 -File.open('itest', 'r+') do |f| # open file for update - lines = f.readlines # read into array of lines - lines.each do |it| # modify lines - it.gsub!(/foo/, 'QQQ') - end - f.pos = 0 # back to start - f.print lines # write out modified lines - f.truncate(f.pos) # truncate to new length -end # file is automatically closed -#----------------------------- -File.open('itest', 'r+') do |f| - out = "" - f.each do |line| - out << line.gsub(/DATE/) {Time.now} - end - f.pos = 0 - f.print out - f.truncate(f.pos) -end - -# @@PLEAC@@_7.11 -File.open('infile', 'r+') do |f| - f.flock File::LOCK_EX - # update file -end -#----------------------------- -File::LOCK_SH # shared lock (for reading) -File::LOCK_EX # exclusive lock (for writing) -File::LOCK_NB # non-blocking request -File::LOCK_UN # free lock -#----------------------------- -unless f.flock File::LOCK_EX | File::LOCK_NB - warn "can't get immediate lock: blocking ..." - f.flock File::LOCK_EX -end -#----------------------------- -File.open('numfile', File::RDWR|File::CREAT) do |f| - f.flock(File::LOCK_EX) - num = f.gets.to_i || 0 - f.pos = 0 - f.truncate 0 - f.puts num + 1q -end - - -# @@PLEAC@@_7.12 -output_handle.sync = true -# Please note that like in Perl, $stderr is already unbuffered -#----------------------------- -#!/usr/bin/ruby -w -# seeme - demo stdio output buffering -$stdout.sync = ARGV.size > 0 -print "Now you don't see it..." -sleep 2 -puts "now you do" -#----------------------------- -$stderr.sync = true -afile.sync = false -#----------------------------- -# assume 'remote_con' is an interactive socket handle, -# but 'disk_file' is a handle to a regular file. -remote_con.sync = true # unbuffer for clarity -disk_file.sync = false # buffered for speed -#----------------------------- -require 'socket' -sock = TCPSocket.new('www.ruby-lang.org', 80) -sock.sync = true -sock.puts "GET /en/ HTTP/1.0 \n\n" -resp = sock.read -print "DOC IS: #{resp}\n" - - -# @@PLEAC@@_7.13 -#----------------------------- -# assumes fh1, fh2, fh2 are oen IO objects -nfound = select([$stdin, fh1, fh2, fh3], nil, nil, 0) -nfound[0].each do |file| - case file - when fh1 - # do something with fh1 - when fh2 - # do something with fh2 - when fh3 - # do something with fh3 - end -end -#----------------------------- -input_files = [] -# repeat next line for all in-files to poll -input_files << fh1 -if nfound = select(input_files, nil, nil, 0) - # input ready on files in nfound[0] -end - - -# @@PLEAC@@_8.0 -#----------------------------- -# datafile is a file or IO object -datafile.readlines.each { |line| - line.chomp! - size = line.length - puts size -} -#----------------------------- -datafile.readlines.each { |line| - puts line.chomp!.length -} -#----------------------------- -lines = datafile.readlines -#----------------------------- -whole_file = file.read -#----------------------------- -# ruby -040 -e 'word = gets; puts "First word is #{word}"' -#----------------------------- -# ruby -ne 'BEGIN { $/="%%\n" }; $_.chomp; puts $_ if( $_=~/Unix/i)' fortune.dat -#----------------------------- -handle.print "one", "two", "three" # "onetwothree" -puts "Baa baa black sheep." # sent to $stdout -#----------------------------- -buffer = handle.read(4096) -rv = buffer.length -#----------------------------- -handle.truncate(length) -open("/tmp#{$$}.pid", 'w') { |handle| handle.truncate(length) } -#----------------------------- -pos = datafile.pos # tell is an alias of pos -puts "I'm #{pos} bytes from the start of datafile" -#----------------------------- -logfile.seek(0, IO::SEEK_END) -datafile.seek(pos) # IO::SEEK_SET is the default -out.seek(-20, IO::SEEK_CUR) -#----------------------------- -written = datafile.syswrite(mystring) -raise RunTimeError unless written == mystring.length -block = infile.sysread(256) # no equivalent to perl offset parameter in sysread -puts "only read #{block.length} bytes" if 256 != block.length -#----------------------------- -pos = handle.sysseek(0, IO::SEEK_CUR) # don't change position - - -# @@PLEAC@@_8.1 -while (line = fh.gets) - line.chomp! - nextline = nil - line.gsub!(/\\$/) { |match| nextline = fh.gets; '' } - if (nextline != nil) - line += nextline - redo - end - # process full record in line here -end -#----------------------------- -# DISTFILES = $(DIST_COMMON) $(SOURCES) $(HEADERS) \ -# $(TEXINFOS) $(INFOS) $(MANS) $(DATA) -# DEP_DISTFILES = $(DIST_COMMON) $(SOURCES) $(HEADERS) \ -# $(TEXINFOS) $(INFO_DEPS) $(MANS) $(DATA) \ -# $(EXTRA_DIST) -#----------------------------- -line.gsub!(/\\\s*$/, '') { - # as before -} - - -# @@PLEAC@@_8.2 -#----------------------------- -count = `wc -l < #{filename}` -fail "wc failed: #{$?}" if $? != 0 -count.chomp! -#----------------------------- -count = 0 -File.open(file, 'r') { |fh| - count += 1 while fh.gets -} -# count now holds the number of lines read -#----------------------------- -count = 0 -while (chunk = file.sysread(2**16)) - count += chunk.count("\n") -end rescue EOFError -#----------------------------- -File.open(filename,'r') { |fh| - count += 1 while fh.gets -} -# count now holds the number of lines read -#----------------------------- -# As ruby doesn't quite have an equivalent to using a for -# statement as in perl, I threw this in -count = File.readlines(filename).size -#----------------------------- -1 while file.gets -count = $. -#----------------------------- -$/ = '' -open(filename, 'r') { |fh| - 1 while fh.gets - para_count = $. -} rescue fail("can't open #{filename}: $!") -#----------------------------- - - -# ^^PLEAC^^_8.3 -#----------------------------- -while (gets) - split.each { |chunk| - # do something with chunk - } -end -#----------------------------- -while (gets) - gsub(/(\w[\w'-]*)/) { |word| - # do something with word - } -end -#----------------------------- -# Make a word frequency count -# normally hashes can be created using {} or just Hash.new -# but we want the default value of an entry to be 0 instead -# of nil. (nil can't be incremented) -seen = Hash.new(0) -while (gets) - gsub(/(\w[\w'-]*)/) { |word| - seen[word.downcase] += 1 - } -end -# output hash in a descending numeric sort of its values -seen.sort { |a,b| b[1] <=> a[1] }.each do |k,v| - printf("%5d %s\n", v, k ) -end - -#----------------------------- -# Line frequency count -seen = Hash.new(0) -while (gets) - seen[$_.downcase] += 1 -end -seen.sort { |a,b| b[1] <=> a[1] }.each do |k,v| - printf("%5d %s\n", v, k ) -end -#----------------------------- - - -# @@PLEAC@@_8.4 -#----------------------------- -# instead of file handle FILE, we can just -# use a string containing the filename -File.readlines(file).each { |line| - # do something with line -} -#----------------------------- -File.readlines(file).reverse_each { |line| - # do something with line -} -#----------------------------- -# the variable lines might have been created -# this way -# lines = File.readlines(file) -# -# normally one would use the reverse_each, but -# if you insist on using a numerical index to -# iterate over the lines array... -(lines.size - 1).downto(0) { |i| - line = lines[i] -} -#----------------------------- -# the second readlines argument is a the -# record separator $/, just like perl, a blank -# separator splits the records into paragraphs -File.readlines(file, '').each { |paragraph| - # do something with paragraph - puts "->Paragraph #{paragraph}" -} -#----------------------------- - - -# @@PLEAC@@_8.6 - -$/ = "%\n"; -srand; - -File.open('/usr/share/fortune/humorists').each do |line| - adage = line if rand($.) < 1 -end - -puts adage; - - -# @@PLEAC@@_8.10 -begin - fh = File.open(file, "r+") - addr = fh.tell unless fh.eof while fh.gets - fh.truncate(addr) -rescue SystemCallError - $stderr.puts "#$!" -end - - -# @@PLEAC@@_9.0 -entry = File.stat("/usr/bin/vi") -entry = File.stat("/usr/bin") -entry = File.stat(INFILE) - -entry = File.stat("/usr/bin/vi") -ctime = entry.ctime -size = entry.size - -f = File.open(filename, "r") - -## There is no -T equivalent in Ruby, but we can still test emptiness -if test(?s, filename) - puts "#{filename} doesn't have text in it." - exit -end - -Dir.new("/usr/bin").each do |filename| - puts "Inside /usr/bin is something called #{filename}" -end - - -# @@PLEAC@@_9.1 -file = File.stat("filename") -readtime, writetime = file.atime, file.mtime -file.utime(readtime, writetime) - -SECONDS_PER_DAY = 60 * 60 * 24 -file = File.stat("filename") -atime, mtime = file.atime, file.mtime - -atime -= 7 * SECONDS_PER_DAY -mtime -= 7 * SECONDS_PER_DAY - -File.utime(atime, mtime, file) -mtime = File.stat(file).mtime -File.utime(Time.new, mtime, file) -File.utime(Time.new, File.stat("testfile").mtime, file) - -#----------------------------- -#!/usr/bin/ruby -w -## uvi - vi a file without changing it's access times - -if ARGV.length != 1 - puts "usage: uvi filename" - exit -end -file = ARGV[0] -atime, mtime = File.stat(file).atime, File.stat(file).mtime -system(ENV["EDITOR"] || "vi", file) -File.utime(atime, mtime, file) -#----------------------------- - - -# @@PLEAC@@_9.2 -File.unlink(FILENAME) - -err_flg = false -filenames.each do |file| - begin - File.unlink(file) - rescue - err_flg = $! - end -end -err_flg and raise "Couldn't unlink all of #{filenames.join(" ")}: #{err_flg}" - -File.unlink(file) - -count = filenames.length -filenames.each do |file| - begin - File.unlink(file) - rescue - count -= 1 - end -end -if count != filenames.length - STDERR.puts "could only delete #{count} of #{filenames.length} files" -end - - -# @@PLEAC@@_9.3 -require "ftools" -File.copy(oldfile, newfile) - -infile = File.open(oldfile, "r") -outfile = File.open(newfile, "w") - -blksize = infile.stat.blksize -# This doesn't handle partial writes or ^Z -# like the Perl version does. -while (line = infile.read(blksize)) - outfile.write(line) -end - -infile.close -outfile.close - -system("cp #{oldfile} #{newfile}") # unix -system("copy #{oldfile} #{newfile}") # dos, vms - -require "ftools" -File.copy("datafile.dat", "datafile.bak") -File.move("datafile.new", "datafile.dat") - - -# @@PLEAC@@_9.4 -$seen = {} # must use global var to be seen inside of method below - -def do_my_thing(filename) - dev, ino = File.stat(filename).dev, File.stat(filename).ino - unless $seen[[dev, ino]] - # do something with $filename because we haven't - # seen it before - end - $seen[[dev, ino]] = $seen[[dev, ino]].to_i + 1 -end - -files.each do |filename| - dev, ino = File.stat(filename).dev, File.stat(filename).ino - if !$seen.has_key?([dev, ino]) - $seen[[dev, ino]] = [] - end - $seen[[dev, ino]].push(filename) -end - -$seen.keys.sort.each do |devino| - ino, dev = devino - if $seen[devino].length > 1 - # $seen[devino] is a list of filenames for the same file - end -end - - -# @@PLEAC@@_9.5 -Dir.open(dirname) do |dir| - dir.each do |file| - # do something with dirname/file - puts file - end -end -# Dir.close is automatic - -# No -T equivalent in Ruby - -dir.each do |file| - next if file =~ /^\.\.?$/ - # ... -end - -def plainfiles(dir) - dh = Dir.open(dir) - dh.entries.grep(/^[^.]/). - map {|file| "#{dir}/#{file}"}. - find_all {|file| test(?f, file)}. - sort -end - - -# @@PLEAC@@_9.6 -list = Dir.glob("*.c") - -dir = Dir.open(path) -files = dir.entries.grep(/\.c$/) -dir.close - -files = Dir.glob("*.c") -files = Dir.open(path).entries.grep(/\.[ch]$/i) - -dir = Dir.new(path) -files = dir.entries.grep(/\.[ch]$/i) - -begin - d = Dir.open(dir) -rescue Errno::ENOENT - raise "Couldn't open #{dir} for reading: #{$!}" -end - -files = [] -d.each do |file| - puts file - next unless file =~ /\.[ch]$/i - - filename = "#{dir}/#{file}" - # There is no -T equivalent in Ruby, but we can still test emptiness - files.push(filename) if test(?s, filename) -end - -dirs.entries.grep(/^\d+$/). - map { |file| [file, "#{path}/#{file}"]} . - select { |file| test(?d, file[1]) }. - sort { |a,b| a[0] <=> b[0] }. - map { |file| file[1] } - - -# @@PLEAC@@_9.7 -require 'find' -Find.find(dirlist) do |file| - # do whatever -end - -require 'find' -argv = ARGV.empty? ? %w{.} : ARGV -Find.find(*argv) do |file| - print file, (test(?d, file) ? "/\n" : "\n") -end - -require 'find' -argv = ARGV.empty? ? %w{.} : ARGV -sum = 0 -Find.find(*argv) do |file| - size = test(?s, file) || 0 - sum += size -end -puts "#{argv.join(' ')} contains #{sum} bytes" - -require 'find' -argv = ARGV.empty? ? %w{.} : ARGV -saved_size, saved_name = -1, "" -Find.find(*argv) do |file| - size = test(?s, file) || 0 - next unless test(?f, file) && size > saved_size - saved_size = size - saved_name = file -end -puts "Biggest file #{saved_name} in #{argv.join(' ')} is #{saved_size}" - -require 'find' -argv = ARGV.empty? ? %w{.} : ARGV -age, name = nil -Find.find(*argv) do |file| - mtime = File.stat(file).mtime - next if age && age > mtime - age = mtime - name = file -end -puts "#{name} #{age}" - -#----------------------------- -#!/usr/bin/ruby -w -# fdirs - find all directories -require 'find' -argv = ARGV.empty? ? %w{.} : ARGV -File.find(*argv) { |file| puts file if test(?d, file) } -#----------------------------- - - -# @@PLEAC@@_9.8 -require 'fileutils' - -puts "Usage #{$0} dir ..." if ARGV.empty? -ARGV.each do |dir| - FileUtils.rmtree(dir) -end - - -# @@PLEAC@@_9.9 -require 'ftools' -names.each do |file| - newname = file - begin - File.move(file, newname) - rescue Errno::EPERM - $stderr.puts "Couldn't rename #{file} to #{newname}: #{$!}" - end -end - -require 'ftools' -op = ARGV.empty? ? (raise "Usage: rename expr [files]\n") : ARGV.shift -argv = ARGV.empty? ? $stdin.readlines.map { |f| f.chomp } : ARGV -argv.each do |file| - was = file - file = eval("file.#{op}") - File.move(was, file) unless was == file -end - - -# @@PLEAC@@_9.10 -base = File.basename(path) -dir = File.dirname(path) -# ruby has no fileparse equivalent -dir, base = File.split(path) -ext = base.scan(/\..*$/).to_s - -path = '/usr/lib/libc.a' -file = File.basename(path) -dir = File.dirname(path) - -puts "dir is #{dir}, file is #{file}" -# dir is /usr/lib, file is libc.a - -path = '/usr/lib/libc.a' -dir, filename = File.split(path) -name, ext = filename.split(/(?=\.)/) -puts "dir is #{dir}, name is #{name}, ext is #{ext}" -# NOTE: The Ruby code prints -# dir is /usr/lib, name is libc, extension is .a -# while the Perl code prints a '/' after the directory name -# dir is /usr/lib/, name is libc, extension is .a - -# No fileparse_set_fstype() equivalent in ruby - -def extension(path) - ext = path.scan(/\..*$/).to_s - ext.sub(/^\./, "") -end - - -# @@PLEAC@@_9.11 -#----------------------------- -#!/usr/bin/ruby -w -# symirror - build spectral forest of symlinks - -require 'find' -require 'fileutils' - -raise "usage: #{$0} realdir mirrordir" unless ARGV.size == 2 - -srcdir,dstdir = ARGV -srcmode = File::stat(srcdir).mode -Dir.mkdir(dstdir, srcmode & 07777) unless test(?d, dstdir) - -# fix relative paths -Dir.chdir(srcdir) {srcdir = Dir.pwd} -Dir.chdir(dstdir) {dstdir = Dir.pwd} - -Find.find(srcdir) do |srcfile| - if test(?d, srcfile) - dest = srcfile.sub(/^#{srcdir}/, dstdir) - dmode = File::stat(srcfile).mode & 07777 - Dir.mkdir(dest, dmode) unless test(?d, dest) - a = Dir["#{srcfile}/*"].reject{|f| test(?d, f)} - FileUtils.ln_s(a, dest) - end -end - - -# @@PLEAC@@_9.12 -# we use the Getopt/Declare library here for convenience: -# http://raa.ruby-lang.org/project/getoptdeclare/ -#----------------------------- -#!/usr/bin/ruby -w -# lst - list sorted directory contents (depth first) - -require 'find' -require 'etc' -require "Getopt/Declare" - -# Note: in the option-spec below there must by at least one hard -# tab in between each -option and its description. For example -# -i <tab> read from stdin - -opts = Getopt::Declare.new(<<'EOPARAM') - ============ - Input Format: - -i read from stdin - ============ - Output Format: - -l long listing - -r reverse listing - ============ - Sort on: (one of) - -m mtime (modify time - default) - {$sort_criteria = :mtime} - -u atime (access time) - {$sort_criteria = :atime} - -c ctime (inode change time) - {$sort_criteria = :ctime} - -s size - {$sort_criteria = :size} - [mutex: -m -u -c -s] - -EOPARAM - -$sort_criteria ||= :mtime -files = {} -DIRS = opts['-i'] ? $stdin.readlines.map{|f|f.chomp!} : ARGV -DIRS.each do |dir| - Find.find(dir) do |ent| - files[ent] = File::stat(ent) - end -end -entries = files.keys.sort_by{|f| files[f].send($sort_criteria)} -entries = entries.reverse unless opts['-r'] - -entries.each do |ent| - unless opts['-l'] - puts ent - next - end - stats = files[ent] - ftime = stats.send($sort_criteria == :size ? :mtime : $sort_criteria) - printf "%6d %04o %6d %8s %8s %8d %s %s\n", - stats.ino, - stats.mode & 07777, - stats.nlink, - ETC::PASSWD[stats.uid].name, - ETC::GROUP[stats.gid].name, - stats.size, - ftime.strftime("%a %b %d %H:%M:%S %Y"), - ent -end - - -# @@PLEAC@@_10.0 -def hello - $greeted += 1 # in Ruby, a variable beginning with $ is global (can be any type of course) - puts "hi there!" -end - -# We need to initialize $greeted before it can be used, because "+=" is waiting a Numeric object -$greeted = 0 -hello # note that appending () is optional to function calls with no parameters - - -# @@PLEAC@@_10.1 -# In Ruby, parameters are named anyway -def hypotenuse(side1, side2) - Math.sqrt(side1**2 + side2**2) # the sqrt function comes from the Math module -end -diag = hypotenuse(3, 4) - -puts hypotenuse(3, 4) - -a = [3, 4] -print hypotenuse(*a) # the star operator will magically convert an Array into a "tuple" - -both = men + women - -# In Ruby, all objects are references, so the same problem arises; we then return a new object -nums = [1.4, 3.5, 6.7] -def int_all(n) - n.collect { |v| v.to_i } -end -ints = int_all(nums) - -nums = [1.4, 3.5, 6.7] -def trunc_em(n) - n.collect! { |v| v.to_i } # the bang-version of collect modifies the object -end -trunc_em(nums) - -# Ruby has two chomp version: -# ``chomp'' chomps the record separator and returns what's expected -# ``chomp!'' does the same but also modifies the parameter object - - -# @@PLEAC@@_10.2 -def somefunc - variable = something # variable is local by default -end - -name, age = ARGV -start = fetch_time - -a, b = pair # will succeed if pair is an Array object (like ARGV is) -c = fetch_time - -# In ruby, run_check can't access a, b, or c until they are -# explicitely defined global (using leading $), even if they are -# both defined in the same scope - -def check_x(x) - y = "whatever" - run_check - if $condition - puts "got $x" - end -end - -# The following will keep a reference to the array, though the -# results will be slightly different from perl: the last element -# of $global_array will be itself an array -def save_array(ary) - $global_array << ary -end - -# The following gives the same results as in Perl for $global_array, -# though it doesn't illustrate anymore the way to keep a reference -# to an object: $global_array is extended with the elements of ary -def save_array(ary) - $global_array += ary -end - - -# @@PLEAC@@_10.3 -# In Ruby, AFAIK a method cannot access "local variables" defined -# upper scope; mostly because everything is an object, so you'll -# do the same by defining an attribute or a static attribute - -# In Ruby the BEGIN also exists: -BEGIN { puts "hello from BEGIN" } -puts "hello from main" -BEGIN { puts "hello from 2nd BEGIN" } -# gives: -# hello from BEGIN -# hello from 2nd BEGIN -# hello from main - -# In Ruby, it can be written as a static method and a static -# variable -class Counter - @@counter = 0 - def Counter.next_counter; @@counter += 1; end -end - -# There is no need of BEGIN since the variable will get -# initialized when parsing -class Counter - @@counter = 42 - def Counter.next_counter; @@counter += 1; end - def Counter.prev_counter; @@counter -= 1; end -end - - -# @@PLEAC@@_10.4 -# You can either get the whole trace as an array of strings, each -# string telling which file, line and method is calling: -caller - -# ...or only the last caller -caller[0] - -# We need to extract just the method name of the backtrace: -def whoami; caller()[0] =~ /in `([^']+)'/ ? $1 : '(anonymous)'; end -def whowasi; caller()[1] =~ /in `([^']+)'/ ? $1 : '(anonymous)'; end - - -# @@PLEAC@@_10.5 -# In Ruby, every value is a reference on an object, thus there is -# no such problem -array_diff(array1, array2) - -def add_vecpair(a1, a2) - results = [] - a1.each_index { |i| results << (a1[i] + a2[i]) } - results -end -a = [1, 2] -b = [5, 8] -c = add_vecpair(a, b) -p c - -# Add this to the beginning of the function to check if we were -# given two arrays -a1.type == Array && a2.type == Array or - raise "usage: add_vecpair array1 array2 (was used with: #{a1.type} #{a2.type})" - - -# @@PLEAC@@_10.6 -# There is no return context in Ruby - - -# @@PLEAC@@_10.7 -# Like in Perl, we need to fake with a hash, but it's dirty :-( -def thefunc(param_args) - args = { 'INCREMENT' => '10s', 'FINISH' => '0', 'START' => 0 } - args.update(param_args) - if (args['INCREMENT'] =~ /m$/ ) - # ..... - end -end - -thefunc({ 'INCREMENT' => '20s', 'START' => '+5m', 'FINISH' => '+30m' }) -thefunc({}) - - -# @@PLEAC@@_10.8 -# there is no "undef" direct equivalent but there is the slice equiv: -a, c = func.indexes(0, 2) - - -# @@PLEAC@@_10.9 -# Ruby has no such limitation: -def somefunc - ary = [] - hash = {} - # ... - return ary, hash -end -arr, dict = somefunc - -array_of_hashes = fn -h1, h2, h3 = fn - - -# @@PLEAC@@_10.10 -return -# or (equivalent) -return nil - - -# @@PLEAC@@_10.11 -# You can't prototype in Ruby regarding types :-( -# Though, you can force the number of arguments: -def func_with_no_arg; end -def func_with_no_arg(); end -def func_with_one_arg(a1); end -def func_with_two_args(a1, a2); end -def func_with_any_number_of_args(*args); end - - -# @@PLEAC@@_10.12 -raise "some message" # raise exception - -begin - val = func -rescue Exception => msg - $stderr.puts "func raised an exception: #{msg}" -end - -# In Ruby the rescue statement uses an exception class, every -# exception which is not matched is still continuing -begin - val = func -rescue FullMoonError - ... -end - - -# @@PLEAC@@_10.13 -# Saving Global Values -# Of course we can just save the value and restore it later: -def print_age - puts "Age is #{$age}" -end - -$age = 18 # global variable -print_age() -if condition - safeage = $age - $age = 23 - print_age() - $age = safeage -end - -# We can also use a method that saves the global variable and -# restores it automatically when the block is left: - -def local(var) - eval("save = #{var.id2name}") - begin - result = yield - ensure - # we want to call this even if we got an exception - eval("#{var.id2name} = save") - end - result -end - -condition = true -$age = 18 -print_age() -if condition - local(:$age) { - $age = 23 - print_age() - } -end -print_age() - -# There is no need to use local() for filehandles or directory -# handles in ruby because filehandles are normal objects. - - -# @@PLEAC@@_10.14 -# In Ruby you may redefine a method [but not overload it :-(] -# just by defining again with the same name. -def foo; puts 'foo'; end -def foo; puts 'bar'; end -foo -#=> bar - -# You can also take a reference to an existing method before -# redefining a new one, using the `alias' keyword -def foo; puts 'foo'; end -alias foo_orig foo -def foo; puts 'bar'; end -foo_orig -foo -#=> foo -#=> bar - -# AFAIK, there is no direct way to create a new method whose name -# comes from a variable, so use "eval" -colors = %w(red blue green yellow orange purple violet) -colors.each { |c| - eval <<-EOS - def #{c}(*a) - "<FONT COLOR='#{c}'>" + a.to_s + "</FONT>" - end - EOS -} - - -# @@PLEAC@@_10.15 -def method_missing(name, *args) - "<FONT COLOR='#{name}'>" + args.join(' ') + "</FONT>" -end -puts chartreuse("stuff") - - -# @@PLEAC@@_10.16 -def outer(arg) - x = arg + 35 - inner = proc { x * 19 } - x + inner.call() -end - - -# @@PLEAC@@_10.17 -#!/usr/bin/ruby -w -# mailsort - sort mbox by different criteria -require 'English' -require 'Date' - -# Objects of class Mail represent a single mail. -class Mail - attr_accessor :no - attr_accessor :subject - attr_accessor :fulltext - attr_accessor :date - - def initialize - @fulltext = "" - @subject = "" - end - - def append(para) - @fulltext << para - end - - # this is called if you call puts(mail) - def to_s - @fulltext - end -end - -# represents a list of mails. -class Mailbox < Array - - Subjectpattern = Regexp.new('Subject:\s*(?:Re:\s*)*(.*)\n') - Datepattern = Regexp.new('Date:\s*(.*)\n') - - # reads mails from open file and stores them - def read(file) - $INPUT_RECORD_SEPARATOR = '' # paragraph reads - msgno = -1 - file.each { |para| - if para =~ /^From/ - mail = Mail.new - mail.no = (msgno += 1) - md = Subjectpattern.match(para) - if md - mail.subject = md[1] - end - md = Datepattern.match(para) - if md - mail.date = DateTime.parse(md[1]) - else - mail.date = DateTime.now - end - self.push(mail) - end - mail.append(para) if mail - } - end - - def sort_by_subject_and_no - self.sort_by { |m| - [m.subject, m.no] - } - end - - # sorts by a list of attributs of mail, given as symbols - def sort_by_attributs(*attrs) - # you can sort an Enumerable by an array of - # values, they would be compared - # from ary[0] to ary[n]t, say: - # ['b',1] > ['a',10] > ['a',9] - self.sort_by { |elem| - attrs.map { |attr| - elem.send(attr) - } - } - end - -end - -mailbox = Mailbox.new -mailbox.read(ARGF) - -# print only subjects sorted by subject and number -for m in mailbox.sort_by_subject_and_no - puts(m.subject) -end - -# print complete mails sorted by date, then subject, then number -for m in mailbox.sort_by_attributs(:date, :subject) - puts(m) -end - - -# @@PLEAC@@_11.7 -def mkcounter(count) - start = count - bundle = { - "NEXT" => proc { count += 1 }, - "PREV" => proc { count -= 1 }, - "RESET" => proc { count = start } - } - bundle["LAST"] = bundle["PREV"] - return bundle -end - -c1 = mkcounter(20) -c2 = mkcounter(77) - -puts "next c1: #{c1["NEXT"].call}" # 21 -puts "next c2: #{c2["NEXT"].call}" # 78 -puts "next c1: #{c1["NEXT"].call}" # 22 -puts "last c1: #{c1["PREV"].call}" # 21 -puts "last c1: #{c1["LAST"].call}" # 20 -puts "old c2: #{c2["RESET"].call}" # 77 - - -# @@PLEAC@@_11.15 -class Binary_tree - def initialize(val) - @value = val - @left = nil - @right = nil - end - - # insert given value into proper point of - # provided tree. If no tree provided, - # use implicit pass by reference aspect of @_ - # to fill one in for our caller. - def insert(val) - if val < @value then - if @left then - @left.insert(val) - else - @left = Binary_tree.new(val) - end - elsif val > @value then - if @right then - @right.insert(val) - else - @right = Binary_tree.new(val) - end - else - puts "double" - # do nothing, no double values - end - end - - # recurse on left child, - # then show current value, - # then recurse on right child. - def in_order - @left.in_order if @left - print @value, " " - @right.in_order if @right - end - - # show current value, - # then recurse on left child, - # then recurse on right child. - def pre_order - print @value, " " - @left.pre_order if @left - @right.pre_order if @right - end - - # recurse on left child, - # then recurse on right child, - # then show current value. - def post_order - @left.post_order if @left - @right.post_order if @right - print @value, " " - end - - # find out whether provided value is in the tree. - # if so, return the node at which the value was found. - # cut down search time by only looking in the correct - # branch, based on current value. - def search(val) - if val == @value then - return self - elsif val < @value then - return @left.search(val) if @left - return nil - else - return @right.search(val) if @right - return nil - end - end -end - -# first generate 20 random inserts -test = Binary_tree.new(0) -for a in 0..20 - test.insert(rand(1000)) -end - -# now dump out the tree all three ways -print "Pre order: "; test.pre_order; puts "" -print "In order: "; test.in_order; puts "" -print "Post order: "; test.post_order; puts "" - -print "search?" -while gets - print test.search($_.to_i) - print "\nsearch?" -end - - -# @@PLEAC@@_12.0 -# class and module names need to have the first letter capitalized -module Alpha - NAME = 'first' -end -module Omega - NAME = 'last' -end -puts "Alpha is #{Alpha::NAME}, Omega is #{Omega::NAME}" - -# ruby doesn't differentiate beteen compile-time and run-time -require 'getoptlong.rb' -require 'getoptlong' # assumes the .rb -require 'cards/poker.rb' -require 'cards/poker' # assumes the .rb -load 'cards/poker' # require only loads the file once - -module Cards - module Poker - @card_deck = Array.new # or @card_deck = [] - def shuffle - end - end -end - - -# @@PLEAC@@_12.1 -# a module exports all of its functions -module Your_Module - def self.function - # this would be called as Your_Module.function - end - - def Your_Module.another - # this is the same as above, but more specific - end -end - -# @@PLEAC@@_12.2 -begin - require 'nonexistent' -rescue LoadError - puts "Couldn't load #{$!}" # $! contains the last error string -end - -# @@PLEAC@@_12.4 -# module variables are private unless access functions are defined -module Alpha - @aa = 10 - @bb = 11 - - def self.put_aa - puts @aa - end - - def self.bb=(val) - @bb = val - end -end - -Alpha.bb = 12 -# Alpha.aa = 10 # error, no aa=method - - -# @@PLEAC@@_12.5 -# caller provides a backtrace of the call stack -module MyModule - def find_caller - caller - end - - def find_caller2(i) - caller(i) # an argument limits the size of the stack returned - end -end - - -# @@PLEAC@@_12.6 -BEGIN { - $logfile = '/tmp/mylog' unless defined? $logfile - $LF = File.open($logfile, 'a') -} - -module Logger - def self.logmsg(msg) - $LF.puts msg - end - - logmsg('startup') -end - -END { - Logger::logmsg('shutdown') - $LF.close -} - - -# @@PLEAC@@_12.7 -#----------------------------- -# results may be different on your system -# % ruby -e "$LOAD_PATH.each_index { |i| printf("%d %s\n", i, $LOAD_PATH[i] } -#0 /usr/local/lib/site_ruby/1.6 -#1 /usr/local/lib/site_ruby/1.6/i386-linux -#2 /usr/local/lib/site_ruby/ -#3 /usr/lib/ruby/1.6 -#4 /usr/lib/ruby/1.6/i136-linux -#5 . -#----------------------------- -# syntax for sh, bash, ksh, or zsh -#$ export RUBYLIB=$HOME/rubylib - -# syntax for csh or tcsh -# % setenv RUBYLIB ~/rubylib -#----------------------------- -$LOAD_PATH.unshift "/projects/spectre/lib"; - - -# @@PLEAC@@_12.8 -# equivalents in ruby are mkmf, SWIG, or Ruby/DL depending on usage - - -# @@PLEAC@@_12.9 -# no equivalent in ruby - - -# @@PLEAC@@_12.10 -# no equivalent in ruby - - -# @@PLEAC@@_12.11 -module FineTime - def self.time - # to be defined later - end -end - - -module FineTime - def self.time - "its a fine time" - end -end - -puts FineTime.time #=> "its a fine time" - - -# @@PLEAC@@_12.12 -def even_only(n) - raise "#{n} is not even" if (n & 1) != 0 # one way to test - # ... -end -def even_only(n) - $stderr.puts "#{n} is not even" if (n & 1) != 0 - # ... -end - - -# @@PLEAC@@_12.17 -# The library archive for ruby is called Ruby Application archive, -# or shorter RAA, and can be found at http://raa.ruby-lang.org. -# A typical library is installed like this: -# % gunzip some-module-4.54.tar.gz -# % tar xf some-module-4.54.tar -# % cd some-module-4.54.tar -# % ruby install.rb config -# % ruby install.rb setup -# get superuser previleges here if needed for next step -# % ruby install.rb install - -# Some modules use a different process, -# you should find details in the documentation -# Here is an example of such a different process -# % ruby extconf.rb -# % make -# % make install - -# If you want the module installed in your own directory: -# For ruby version specific libraries -# % ruby install.rb config --site-ruby=~/lib -# For version independent libraries -# % ruby install.rb config --site-ruby-common=~/lib - -# Information about possible options for config -# % ruby install.rb --help - -# If you have your own complete distribution -# % ruby install.rb --prefix=path=~/ruby-private - - -# @@PLEAC@@_13.0 -# Classes and objects in Ruby are rather straigthforward -class Person - # Class variables (also called static attributes) are prefixed by @@ - @@person_counter=0 - - # object constructor - def initialize(age, name, alive = true) # Default arg like in C++ - @age, @name, @alive = age, name, alive # Object attributes are prefixed by '@' - @@person_counter += 1 - # There is no '++' operator in Ruby. The '++'/'--' operators are in fact - # hidden assignments which affect variables, not objects. You cannot accomplish - # assignment via method. Since everything in Ruby is object, '++' and '--' - # contradict Ruby OO ideology. Instead '-=' and '+=' are used. - end - - attr_accessor :name, :age # This creates setter and getter methods for @name - # and @age. See 13.3 for detailes. - - # methods modifying the receiver object usually have the '!' suffix - def die! - @alive = false - puts "#{@name} has died at the age of #{@age}." - @alive - end - - def kill(anotherPerson) - print @name, ' is killing ', anotherPerson.name, ".\n" - anotherPerson.die! - end - - # methods used as queries - # usually have the '?' suffix - def alive? - @alive && true - end - - def year_of_birth - Time.now.year - @age - end - - # Class method (also called static method) - def Person.number_of_people - @@person_counter - end -end - -# Using the class: -# Create objects of class Person -lecter = Person.new(47, 'Hannibal') -starling = Person.new(29, 'Clarice', true) -pazzi = Person.new(40, 'Rinaldo', true) - -# Calling a class method -print "There are ", Person.number_of_people, " Person objects\n" - -print pazzi.name, ' is ', (pazzi.alive?) ? 'alive' : 'dead', ".\n" -lecter.kill(pazzi) -print pazzi.name, ' is ', (pazzi.alive?) ? 'alive' : 'dead', ".\n" - -print starling.name , ' was born in ', starling.year_of_birth, "\n" - - -# @@PLEAC@@_13.1 -# If you don't need any initialisation in the constructor, -# you don't need to write a constructor. -class MyClass -end - -class MyClass - def initialize - @start = Time.new - @age = 0 - end -end - -class MyClass - def initialize(inithash) - @start = Time.new - @age = 0 - for key, value in inithash - instance_variable_set("@#{key}", value) - end - end -end - -# @@PLEAC@@_13.2 -# Objects are destroyed by the garbage collector. -# The time of destroying is not predictable. -# The ruby garbage collector can handle circular references, -# so there is no need to write destructor for that. - -# There is no direct support for destructor. -# You can call a custom function, or more specific a proc object, when the -# garbage collector is about to destruct the object, but it is unpredictable -# when this occurs. -# Also if such a finalizer object has a reference to the orignal object, -# this may prevent the original object to get garbage collected. -# Because of this problem the finalize method below is -# a class method and not a instance method. -# So if you need to free resources for an object, like -# closing a socket or kill a spawned subprocess, -# you should do it explicitly. - -class MyClass - def initialize - ObjectSpace.define_finalizer(self, - self.class.method(:finalize).to_proc) - end - def MyClass.finalize(id) - puts "Object #{id} dying at #{Time.new}" - end -end - -# test code -3.times { - MyClass.new -} -ObjectSpace.garbage_collect - - -# @@PLEAC@@_13.3 -# You can write getter and setter methods in a natural way: -class Person - def name - @name - end - def name=(name) - @name = name - end -end - -# But there is a better and shorter way -class Person - attr_reader :age - attr_writer :name - # attr_reader and attr_writer are actually methods in class Class - # which set getter and setter methods for you. -end - -# There is also attr_accessor to create both setters and getters -class Person - attr_accessor :age, :name -end - - -# @@PLEAC@@_13.4 -class Person - # Class variables (also called static attributes) are prefixed by @@ - @@person_counter = 0 - - def Person.population - @@person_counter - end - def initialize - @@person_counter += 1 - ObjectSpace.define_finalizer(self, - self.class.method(:finalize).to_proc) - end - def Person.finalize(id) - @@person_counter -= 1 - end -end -people = [] -10.times { - people.push(Person.new) -} -printf("There are %d people alive", Person.population) - - -FixedArray.class_max_bounds = 100 -alpha = FixedArray.new -puts "Bound on alpha is #{alpha.max_bounds}" - -beta = FixedArray.new -beta.max_bounds = 50 # calls the instance method -beta.class.class_max_bounds = 50 # alternative, calls the class method -puts "Bound on alpha is #{alpha.max_bounds}" - -class FixedArray - @@bounds = 7 - - def max_bounds - @@max_bounds - end - # instance method, which sets the class variable - def max_bounds=(value) - @@max_bounds = value - end - # class method. This can only be called on a class, - # but not on the instances - def FixedArray.class_max_bounds=(value) - @@max_bounds = value - end -end - - -# @@PLEAC@@_13.5 -PersonStruct = Struct.new("Person", :name, :age, :peers) -# creates a class "Person::Struct", which is accessiable with the -# constant "PersonStruct" -p = PersonStruct.new -p = Struct::Person.new # alternative using the classname -p.name = "Jason Smythe" -p.age = 13 -p.peers = ["Wilbur", "Ralph", "Fred"] -p[:peers] = ["Wilbur", "Ralph", "Fred"] # alternative access using symbol -p["peers"] = ["Wilbur", "Ralph", "Fred"] # alternative access using name of field -p[2] = ["Wilbur", "Ralph", "Fred"] # alternative access using index of field -puts "At age #{p.age}, #{p.name}'s first friend is #{p.peers[0]}" - -# The fields of a struct have no special type, like other ruby variables -# you can put any objects in. Therefore the discussions how to specify -# the types of the fields do not apply to ruby. - -FamilyStruct = Struct.new("Family", :head, :address, :members) -folks = FamilyStruct.new -folks.head = PersonStruct.new -dad = folks.head -dad.name = "John" -dad.age = 34 - -# supply of own accessor method for the struct for error checking -class PersonStruct - def age=(value) - if !value.kind_of?(Integer) - raise(ArgumentError, "Age #{value} isn't an Integer") - elsif value > 150 - raise(ArgumentError, "Age #{value} is unreasonable") - end - @age = value - end -end - - -# @@PLEAC@@_13.6 -# The ruby Object class defines a dup and a clone method. -# The dup method is recommended for prototype object creation. -# The default implementation makes a shallow copy, -# but each class can override it, for example to make a deep copy. - -# If you want to call 'new' directly on the instances, -# you can create a instance method "new", which returns a new duplicate. -# This method is distinct from the class method new. -# -class A - def new - dup - end -end - -ob1 = A.new -# later on -ob2 = ob1.new - - -# @@PLEAC@@_13.7 -methname = 'flicker' -obj.send(methname, 10) # calls obj.flicker(10) - -# call three methods on the object, by name -['start', 'run', 'stop'].each do |method_string| - obj.send(method_string) -end - -# Another way is to create a Method object -method_obj = obj.method('flicker') -# And then call it -method_obj.call(10) - - -# @@PLEAC@@_13.8 -# All classes in Ruby inherit from class Object -# and thus all objects share methods defined in this class - -# the class of the object -puts any_object.type - -# Ruby classes are actually objects of class Class and they -# respond to methods defined in Object class as well - -# the superclass of this class -puts any_object.class.superclass - -# ask an object whether it is an instance of particular class -n = 4.7 -puts n.instance_of?(Float) # true -puts n.instance_of?(Numeric) # false - -# ask an object whether it is an instance of class, one of the -# superclasses of the object, or modules included in it -puts n.kind_of?(Float) # true (the class) -puts n.kind_of?(Numeric) # true (an ancestor class) -puts n.kind_of?(Comparable) # true (a mixin module) -puts n.kind_of?(String) # false - -# ask an object whether it can respond to a particular method -puts n.respond_to?('+') # true -puts n.respond_to?('length') # false - -# all methods an object can respond to -'just a string'.methods.each { |m| puts m } - - -# @@PLEAC@@_13.9 -# Actually any class in Ruby is inheritable -class Person - attr_accessor :age, :name - def initialize - @name - @age - end -end -#----------------------------- -dude = Person.new -dude.name = 'Jason' -dude.age = 23 -printf "%s is age %d.\n", dude.name, dude.age -#----------------------------- -# Inheriting from Person -class Employee < Person - attr_accessor :salary -end -#----------------------------- -empl = Employee.new -empl.name = 'Jason' -empl.age = 23 -empl.salary = 200 -printf "%s is age %d, the salary is %d.\n", empl.name, empl.age, empl.salary -#----------------------------- -# Any built-in class can be inherited the same way -class WeirdString < String - def initialize(obj) - super obj - end - def +(anotherObj) # + method in this class is overridden - # to return the sum of string lengths - self.length + anotherObj.length # 'self' can be omitted - end -end -#----------------------------- -a = WeirdString.new('hello') -b = WeirdString.new('bye') - -puts a + b # the overridden + -#=> 8 -puts a.length # method from the superclass, String -#=> 5 - - -# @@PLEAC@@_13.11 -# In ruby you can override the method_missing method -# to have a solution similar to perls AUTOLOAD. -class Person - - def initialize - @ok_fields = %w(name age peers parent) - end - - def valid_attribute?(name) - @ok_fields.include?(name) - end - - def method_missing(namesymbol, *params) - name = namesymbol.to_s - return if name =~ /^A-Z/ - if name.to_s[-1] == ('='[0]) # we have a setter - isSetter = true - name.sub!(/=$/, '') - end - if valid_attribute?(name) - if isSetter - instance_variable_set("@#{name}", *params) - else - instance_variable_get("@#{name}", *params) - end - else - # if no annestor is responsible, - # the Object class will throw a NoMethodError exception - super(namesymbol, *params) - end - end - - def new - kid = Person.new - kid.parent = self - kid - end - -end - -dad = Person.new -dad.name = "Jason" -dad.age = 23 -kid = dad.new -kid.name = "Rachel" -kid.age = 2 -puts "Kid's parent is #{kid.parent.name}" -puts dad -puts kid - -class Employee < Person - def initialize - super - @ok_fields.push("salary", "boss") - end - def ok_fields - @ok_fields - end -end - - -# @@PLEAC@@_13.13 -# The ruby garbage collector pretends to cope with circular structures. -# You can test it with this code: -class RingNode - attr_accessor :next - attr_accessor :prev - attr_reader :name - - def initialize(aName) - @name = aName - ObjectSpace.define_finalizer(self, - self.class.method(:finalize).to_proc) - end - - def RingNode.finalize(id) - puts "Node #{id} dying" - end - - def RingNode.show_all_objects - ObjectSpace.each_object {|id| - puts id.name if id.class == RingNode - } - end -end - -def create_test - a = RingNode.new("Node A") - b = RingNode.new("Node B") - c = RingNode.new("Node C") - a.next = b - b.next = c - c.next = a - a.prev = c - c.prev = b - b.prev = a - - a = nil - b = nil - c = nil -end - -create_test -RingNode.show_all_objects -ObjectSpace.garbage_collect -puts "After garbage collection" -RingNode.show_all_objects - - -# @@PLEAC@@_13.14 -class String - def <=>(other) - self.casecmp other - end -end - -# There is no way to directly overload the '""' (stringify) -# operator in Ruby. However, by convention, classes which -# can reasonably be converted to a String will define a -# 'to_s' method as in the TimeNumber class defined below. -# The 'puts' method will automatcally call an object's -# 'to_s' method as is demonstrated below. -# Furthermore, if a class defines a to_str method, an object of that -# class can be used most any place where the interpreter is looking -# for a String value. - -#--------------------------------------- -# NOTE: Ruby has a builtin Time class which would usually be used -# to manipulate time objects, the following is supplied for -# educational purposes to demonstrate operator overloading. -# -class TimeNumber - attr_accessor :hours,:minutes,:seconds - def initialize( hours, minutes, seconds) - @hours = hours - @minutes = minutes - @seconds = seconds - end - - def to_s - return sprintf( "%d:%02d:%02d", @hours, @minutes, @seconds) - end - - def to_str - to_s - end - - def +( other) - seconds = @seconds + other.seconds - minutes = @minutes + other.minutes - hours = @hours + other.hours - if seconds >= 60 - seconds %= 60 - minutes += 1 - end - if minutes >= 60 - minutes %= 60 - hours += 1 - end - return TimeNumber.new(hours, minutes, seconds) - end - - def -(other) - raise NotImplementedError - end - - def *(other) - raise NotImplementedError - end - - def /( other) - raise NotImplementedError - end -end - -t1 = TimeNumber.new(0, 58, 59) -sec = TimeNumber.new(0, 0, 1) -min = TimeNumber.new(0, 1, 0) -puts t1 + sec + min + min - -#----------------------------- -# StrNum class example: Ruby's builtin String class already has the -# capabilities outlined in StrNum Perl example, however the '*' operator -# on Ruby's String class acts differently: It creates a string which -# is the original string repeated N times. -# -# Using Ruby's String class as is in this example: -x = "Red"; y = "Black" -z = x+y -r = z*3 # r is "RedBlackRedBlackRedBlack" -puts "values are #{x}, #{y}, #{z}, and #{r}" -print "#{x} is ", x < y ? "LT" : "GE", " #{y}\n" -# prints: -# values are Red, Black, RedBlack, and RedBlackRedBlackRedBlack -# Red is GE Black - -#----------------------------- -class FixNum - REGEX = /(\.\d*)/ - DEFAULT_PLACES = 0 - attr_accessor :value, :places - def initialize(value, places = nil) - @value = value - if places - @places = places - else - m = REGEX.match(value.to_s) - if m - @places = m[0].length - 1 - else - @places = DEFAULT_PLACES - end - end - end - - def +(other) - FixNum.new(@value + other.value, max(@places, other.places)) - end - - def *(other) - FixNum.new(@value * other.value, max(@places, other.places)) - end - - def /(other) - puts "Divide: #{@value.to_f/other.value.to_f}" - result = FixNum.new(@value.to_f/other.value.to_f) - result.places = max(result.places,other.places) - result - end - - def to_s - sprintf("STR%s: %.*f", self.class.to_s , @places, @value) #. - end - - def to_str - to_s - end - - def to_i #convert to int - @value.to_i - end - - def to_f #convert to float` - @value.to_f - end - - private - def max(a,b) - a > b ? a : b - end -end - -def demo() - x = FixNum.new(40) - y = FixNum.new(12, 0) - - puts "sum of #{x} and #{y} is #{x+y}" - puts "product of #{x} and #{y} is #{x*y}" - - z = x/y - puts "#{z} has #{z.places} places" - unless z.places - z.places = 2 - end - - puts "div of #{x} by #{y} is #{z}" - puts "square of that is #{z*z}" -end - -if __FILE__ == $0 - demo() -end - - -# @@PLEAC@@_14.1 -# There are dbm, sdbm, gdbm modules -# and the bdb module for accessing the berkeley db -# sdbm seem to be available on the most systems, -# so we use it here -# -require "sdbm" -SDBM.open("filename", 0666) { |dbobj| - # raises exception if open error - - # the returned sdbm-dbobj has most of the methods of a hash - v = dbobj["key"] - dbobj["key"] = "newvalue" - if dbobj.has_key?("key") - # ... - end - dbobj.delete("key2") -} -# database is open only inside the block. - -# It is also possible to use a open .. close pair: -dbobj = SDBM.open("filename", 0666) -#.. do something with dbobj -dbobj.close - -#!/usr/bin/ruby -w -# userstats - generate statistics on who is logged in -# call with usernames as argument to display the totals -# for the given usernames, call with "ALL" to display all users - -require "sdbm" -filename = '/tmp/userstats.db' -SDBM.open(filename, 0666) { |dbobj| - if ARGV.length > 0 - if ARGV[0] == "ALL" - # ARGV is constant, so we need the variable userlist - userlist = dbobj.keys().sort() - else - userlist = ARGV - end - userlist.each { |user| - print "#{user}\t#{dbobj[user]}\n" - } - else - who = `who` - who.split("\n").each { |line| - md = /^(\S+)/.match(line) - raise "Bad line from who: #{line}" unless md - # sdbm stores only strings, so "+=" doesn't work, - # we need to convert them expicitly back to integer. - if dbobj.has_key?(md[0]) - dbobj[md[0]] = dbobj[md[0]].to_i + 1 - else - dbobj[md[0]] = "1" - end - } - end -} - - -# @@PLEAC@@_14.2 -# using open and clear -dbobj = SDBM.open("filename", 0666) -dbobj.clear() -dbobj.close() -# deleting file and recreating it -# the filenames depend on the flavor of dbm you use, -# for example sdbm has two files named filename.pag and filename.dir, -# so you need to delete both files -begin - File.delete("filename") - # raises Exception if not exist - dbobj = SDBM.open("filename", 0666) -rescue - # add error handling here -end - - -# @@PLEAC@@_14.3 -# sdbm2gdbm: converts sdbm database to a gdbm database -require "sdbm" -require "gdbm" - -unless ARGV.length == 2 - fail "usage: sdbm2gdbm infile outfile" -end -infile = ARGV[0] -outfile = ARGV[1] - -sdb = SDBM.open(infile) -gdb = GDBM.open(outfile, 0666) -sdb.each { |key, val| - gdb[key] = val -} -gdb.close -sdb.close - - -# @@PLEAC@@_14.4 -#!/usr/bin/ruby -w -# dbmmerge: merges two dbm databases -require "sdbm" - -unless ARGV.length == 3 - fail "usage: dbmmerge indb1 indb2 outdb" -end -infile1 = ARGV[0] -infile2 = ARGV[0] -outfile = ARGV[2] - -in1 = SDBM.open(infile1, nil) -in2 = SDBM.open(infile2, nil) -outdb = SDBM.open(outfile, 0666) - -[in1, in2].each { |indb| - indb.each { |key, val| - if outdb.has_key?(key) - # decide which value to set. - # set outdb[key] if necessary - else - outdb[key] = val - end - } -} -in1.close -in2.close -outdb.close - - -# @@PLEAC@@_14.7 -# we write a tie method that extends the Array class. -# It reads the file into the memory, executes the code block -# in which you can manipulate the array as needed, and writes -# the array back to the file after the end of the block execution -class Array - def tie(filename, flags) - File.open(filename, flags) { |f| - f.each_line { |line| - self.push(line.chomp) - } - yield - f.rewind - each { |line| - if line - f.puts(line) - else - f.puts "" - end - } - } - end -end - -array = Array.new -array.tie("/tmp/textfile.txt", File::RDWR|File::CREAT) { - array[4] = "a new line 4" -} - -# The tied array can be manipulated like a normal array, -# so there is no need for a special API, and the recno_demo program -# to demonstrate is API is useless - - -# tied array demo: show how to use array with a tied file -filename = "db_file.txt" -lines = Array.new -File.unlink(filename) if File.exists?(filename) -lines.tie(filename, File::RDWR | File::CREAT) { - # first create a textfile to play with - lines[0] = "zero" - lines[1] = "one" - lines[2] = "two" - lines[3] = "three" - lines[4] = "four" - - # print the records in order. - # Opposed to perl, the tied array behaves exactly as a normal array - puts "\nOriginal" - for i in 0..(lines.length-1) - puts "#{i}: #{lines[i]}" - end - - #use push and pop - a = lines.pop - lines.push("last") - puts("The last line was [#{a}]") - - #use shift and unshift - a = lines.shift - lines.unshift("first") - puts("The first line was [#{a}]") - - # add record after record 2 - i = 2 - lines.insert(i + 1, "Newbie") - - # add record before record one - i = 1 - lines.insert(i, "New One") - - # delete record 3 - lines.delete_at(3) - - #now print the records in reverse order - puts "\nReverse" - (lines.length - 1).downto(0){ |i| - puts "#{i}: #{lines[i]}" - } - -} - - -# @@PLEAC@@_14.8 -# example to store complex data in a database -# uses marshall from the standard library -require "sdbm" -db = SDBM.open("pleac14-8-database", 0666) - -# convert the Objects into strings and back by using the Marshal module. -# Most normal objects can be converted out of the box, -# but not special things like procedure objects, -# IO instance variables, singleton objects - -db["Tom Christiansen"] = Marshal.dump(["book author", "tchrist@perl.com"]) -db["Tom Boutell"] = Marshal.dump(["shareware author", -"boutell@boutell.com"]) - -name1 = "Tom Christiansen" -name2 = "Tom Boutell" - -tom1 = Marshal.load(db[name1]) -tom2 = Marshal.load(db[name2]) - -puts "Two Toming: #{tom1} #{tom2}" - -if tom1[0] == tom2[0] && tom1[1] == tom2[1] - puts "You're having runtime fun with one Tom made two." -else - puts "No two Toms are ever alike" -end - -# To change parts of an entry, get the whole entry, change the parts, -# and save the whole entry back -entry = Marshal.load(db["Tom Boutell"]) -entry[0] = "Poet Programmer" -db["Tom Boutell"] = Marshal.dump(entry) -db.close - - -# @@PLEAC@@_14.9 -# example to make data persistent -# uses Marshal from the standard lib -# Stores the data in a simple file, -# see 14.8 on how to store it in a dbm file - -# The BEGIN block is executed before the rest of the script -# we use global variables here because local variables -# will go out of scope and are not accessible from the main script - -BEGIN { - $persistent_store = "persitence.dat" - begin - File.open($persistent_store) do |f| - $stringvariable1 = Marshal.load(f) - $arrayvariable2 = Marshal.load(f) - end - rescue - puts "Can not open #{$persistent_store}" - # Initialisation if this script runs the first time - $stringvariable1 = "" - $arrayvariable2 = [] - end -} - -END { - File.open($persistent_store, "w+") do |f| - Marshal.dump($stringvariable1, f) - Marshal.dump($arrayvariable2, f) - end -} - -# simple test program -puts $stringvariable1 -puts $arrayvariable2 -$stringvariable1 = "Hello World" -$arrayvariable2.push(5) -puts $stringvariable1 -puts $arrayvariable2 - - -# @@PLEAC@@_14.10 -#!/usr/bin/ruby -w -# Ruby has a dbi module with an architecture similar -# to the Perl dbi module: the dbi module provides an unified -# interface and uses specialized drivers for each dbms vendor -# -begin - DBI.connect("DBI:driver:driverspecific", "username", "auth") { - |dbh| - - dbh.do(SQL1) - - dbh.prepare(SQL2){ |sth| - sth.execute - sth.fetch {|row| - # ... - } - } # end of block finishes the statement handle - } # end of block closes the database connection -rescue DBI::DatabaseError => e - puts "dbi error occurred" - puts "Error code: #{e.err}" - puts "Error message: #{e.errstr}" -end - -#!/usr/bin/ruby -w -# dbusers - example for mysql which creates a table, -# fills it with values, retrieves the values back, -# and finally destroys the table. - -require "dbi" - -# replacement for the User::pwnt module -def getpwent - result = [] - File.open("/etc/passwd") {|file| - file.each_line {|line| - next if line.match(/^#/) - cols = line.split(":") - result.push([cols[2], cols[0]]) - } - } - result -end - -begin - DBI.connect("DBI:Mysql:pleacdatabase", "pleac", "pleacpassword") { - |conn| - - conn.do("CREATE TABLE users (uid INT, login CHAR(8))") - - users = getpwent - - conn.prepare("INSERT INTO users VALUES (?,?)") {|sth| - users.each {|entry| - sth.execute(entry[0], entry[1]) - } - } - - conn.execute("SELECT uid, login FROM users WHERE uid < 50") {|sth| - sth.fetch {|row| - puts row.collect {|col| - if col.nil? - "(null)" - else - col - end - }.join(", ") - } - } - - conn.do("DROP TABLE users") - } -rescue DBI::DatabaseError => e - puts "dbi error occurred" - puts "Error code: #{e.err}" - puts "Error message: #{e.errstr}" -end - - -# @@PLEAC@@_15.1 -# This test program demonstrates parsing program arguments. -# It uses the optparse library, which is included with ruby 1.8 -# It handles classic unix style and gnu style options -require 'optparse' - -@debugmode = false -@verbose = false - -ARGV.options do |opts| - opts.banner = "Usage: ruby #{$0} [OPTIONS] INPUTFILES" - - opts.on("-h", "--help", "show this message") { - puts opts - exit - } - # The OptionParser#on method is called with a specification of short - # options, of long options, a data type spezification and user help - # messages for this option. - # The method analyses the given parameter and decides what it is, - # so you can leave out the long option if you don't need it - opts.on("-v", "--[no-]verbose=[FLAG]", TrueClass, "run verbosly") { - |@verbose| # sets @verbose to true or false - } - opts.on("-D", "--DEBUG", TrueClass, "turns on debug mode" ){ - |@debugmode| # sets @debugmode to true - } - opts.on("-c", "--count=NUMBER", Integer, "how many times we do it" ){ - |@count| # sets @count to given integer - } - opts.on("-o", "--output=FILE", String, "file to write output to"){ - |@outputfile| # sets @outputfile to given string - } - opts.parse! -end - -# example to use the options in the main program -puts "Verbose is on" if @verbose -puts "Debugmode is on" if @debugmode -puts "Outfile is #{@outputfile}" if defined? @outputfile -puts "Count is #{@count}" if defined? @count -ARGV.each { |param| - puts "Got parameter #{param}" -} - - -# @@PLEAC@@_15.4 -buf = "\0" * 8 -$stdout.ioctl(0x5413, buf) -ws_row, ws_col, ws_xpixel, ws_ypixel = buf.unpack("S4") - -raise "You must have at least 20 characters" unless ws_col >= 20 -max = 0 -values = (1..5).collect { rand(20) } # generate an array[5] of rand values -for i in values - max = i if max < i -end -ratio = Float(ws_col-12)/max # chars per unit -for i in values - printf "%8.1f %s\n", i, "*" * (ratio*i) -end - -# gives, for example: -# 15.0 ******************************* -# 10.0 ********************* -# 5.0 ********** -# 14.0 ***************************** -# 18.0 ************************************** - - -# @@PLEAC@@_16.1 -output = `program args` # collect output into one multiline string -output = `program args`.split # collect output into array, one line per -element - -readme = IO.popen("ls") -output = "" -while readme.gets do - output += $_ -end -readme.close - -`fsck -y /dev/rsd1a` # BAD AND SCARY in Perl because it's managed by the shell - # I donna in Ruby ... - -# so the "clean and secure" version -readme, writeme = IO.pipe -pid = fork { - # child - $stdout = writeme - readme.close - exec('find', '..') -} -# parent -Process.waitpid(pid, 0) -writeme.close -while readme.gets do - # do something with $_ -end - - -# @@PLEAC@@_16.2 -status = system("xemacs #{myfile}") - -status = system("xemacs", myfile) - -system("cmd1 args | cmd2 | cmd3 >outfile") -system("cmd args <infile >outfile 2>errfile") - -# stop if the command fails -raise "$program exited funny: #{$?}" unless system("cmd", "args1", "args2") - -# get the value of the signal sent to the child -# even if it is a SIGINT or SIGQUIT -system(arglist) -raise "program killed by signal #{$?}" if ($? & 127) != 0 - -pid = fork { - trap("SIGINT", "IGNORE") - exec("sleep", "10") -} -trap ("SIGINT") { - puts "Tsk tsk, no process interruptus" -} -Process.waitpid(pid, 0) - -# Ruby doesn't permit to lie to the program called by a 'system'. -# (ie specify what return argv[0] in C, $0 in Perl/Ruby ...) -# A (dirty) way is to create a link (under Unix), run this link and -# erase it. Somebody has a best idea ? - - -# @@PLEAC@@_16.3 -exec("archive *.data") - -exec("archive", "accounting.data") - -exec("archive accounting.data") - - -# @@PLEAC@@_16.4 -# read the output of a program -IO.popen("ls") {|readme| - while readme.gets do - # ... - end -} -# or -readme = IO.popen("ls") -while readme.gets do - # ... -end -readme.close - -# "write" in a program -IO.popen("cmd args","w") {|pipe| - pipe.puts("data") - pipe.puts("foo") -} - -# close wait for the end of the process -read = IO.popen("sleep 10000") # child goes to sleep -read.close # and the parent goes to lala land - -writeme = IO.popen("cmd args", "w") -writeme.puts "hello" # program will get hello\n on STDIN -writeme.close # program will get EOF on STDIN - -# send in a pager (eg less) all output -$stdout = IO.popen("/usr/bin/less","w") -print "huge string\n" * 10000 - - -# @@PLEAC@@_16.5 -#----------------------------- -def head(lines = 20) - pid = open("|-","w") - if pid == nil - return - else - while gets() do - pid.print - lines -= 1 - break if lines == 0 - end - end - exit -end - -head(100) -while gets() do - print -end -#----------------------------- -1: > Welcome to Linux, version 2.0.33 on a i686 - -2: > - -3: > "The software required `Windows 95 or better', - -4: > so I installed Linux." -#----------------------------- -> 1: Welcome to Linux, Kernel version 2.0.33 on a i686 - -> 2: - -> 3: "The software required `Windows 95 or better', - -> 4: so I installed Linux." -#----------------------------- -#!/usr/bin/ruby -# qnumcat - demo additive output filters - -def number() - pid = open("|-","w") - if pid == nil - return - else - while gets() do pid.printf("%d: %s", $., $_); end - end - exit -end - -def quote() - pid = open("|-","w") - if pid == nil - return - else - while gets() do pid.print "> #{$_}" end - end - exit -end - -number() -quote() - -while gets() do - print -end -$stdout.close -exit - - -# @@PLEAC@@_16.6 -ARGV.map! { |arg| - arg =~ /\.(gz|Z)$/ ? "|gzip -dc #{arg}" : arg -} -for file in ARGV - fh = open(file) - while fh.gets() do - # ....... - end -end -#----------------------------- -ARGV.map! { |arg| - arg =~ %r#^\w+://# ? "|GET #{arg}" : arg # -} -for file in ARGV - fh = open(file) - while fh.gets() do - # ....... - end -end -#----------------------------- -pwdinfo = (`domainname` =~ /^(\(none\))?$/) ? '/etc/passwd' : '|ypcat passwd'; -pwd = open(pwdinfo); -#----------------------------- -puts "File, please? "; -file = gets().chomp(); -fh = open(file); - - -# @@PLEAC@@_16.7 -output = `cmd 2>&1` # with backticks -# or -ph = open("|cmd 2>&1") # with an open pipe -while ph.gets() { } # plus a read -#----------------------------- -output = `cmd 2>/dev/null` # with backticks -# or -ph = open("|cmd 2>/dev/null") # with an open pipe -while ph.gets() { } # plus a read -#----------------------------- -output = `cmd 2>&1 1>/dev/null` # with backticks -# or -ph = open("|cmd 2>&1 1>/dev/null") # with an open pipe -while ph.gets() { } # plus a read -#----------------------------- -output = `cmd 3>&1 1>&2 2>&3 3>&-` # with backticks -# or -ph = open("|cmd 3>&1 1>&2 2>&3 3>&-") # with an open pipe -while ph.gets() { } # plus a read -#----------------------------- -system("program args 1>/tmp/program.stdout 2>/tmp/program.stderr") -#----------------------------- -output = `cmd 3>&1 1>&2 2>&3 3>&-` -#----------------------------- -fd3 = fd1 -fd1 = fd2 -fd2 = fd3 -fd3 = nil -#----------------------------- -system("prog args 1>tmpfile 2>&1") -system("prog args 2>&1 1>tmpfile") -#----------------------------- -# system ("prog args 1>tmpfile 2>&1") -fd1 = "tmpfile" # change stdout destination first -fd2 = fd1 # now point stderr there, too -#----------------------------- -# system("prog args 2>&1 1>tmpfile") -fd2 = fd1 # stderr same destination as stdout -fd1 = "tmpfile" # but change stdout destination -#----------------------------- -# It is often better not to rely on the shell, -# because of portability, possible security problems -# and bigger resource usage. So, it is often better to use the open3 library. -# See below for an example. -# opening stdin, stdout, stderr -require "open3" -stdin, stdout, stderr = Open3.popen('cmd') - - -# @@PLEAC@@_16.8 -#----------------------------- -# Contrary to perl, we don't need to use a module in Ruby -fh = Kernel.open("|" + program, "w+") -fh.puts "here's your input\n" -output = fh.gets() -fh.close() -#----------------------------- -Kernel.open("|program"),"w+") # RIGHT ! -#----------------------------- -# Ruby has already object methods for I/O handles -#----------------------------- -begin - fh = Kernel.open("|" + program_and_options, "w+") -rescue - if ($@ ~= /^open/) - $stderr.puts "open failed : #{$!} \n #{$@} \n" - break - end - raise # reraise unforseen exception -end - - -# @@PLEAC@@_16.13 -#% kill -l -#HUP INT QUIT ILL TRAP ABRT BUS FPE KILL USR1 SEGV USR2 PIPE -#ALRM TERM CHLD CONT STOP TSTP TTIN TTOU URG XCPU XFSZ VTALRM -#PROF WINCH POLL PWR -#----------------------------- -#% ruby -e 'puts Signal.list.keys.join(" ")' -#PWR USR1 BUS USR2 TERM SEGV KILL POLL STOP SYS TRAP IOT HUP INT # -#WINCH XCPU TTIN CLD TSTP FPE IO TTOU PROF CHLD CONT PIPE ABRT -#VTALRM QUIT ILL XFSZ URG ALRM -#----------------------------- -# After that, the perl script create an hash equivalent to Signal.list, -# and an array. The array can be obtained by : -signame = [] -Signal.list.each { |name, i| signame[i] = name } - - -# @@PLEAC@@_16.14 -Process.kill(9, pid) # send $pid a signal 9 -Process.kill(-1, Process.getpgrp()) # send whole job a signal 1 -Process.kill("USR1", $$) # send myself a SIGUSR1 -Process.kill("HUP", pid1, pid2, pid3) # send a SIGHUP to processes in @pids -#----------------------------- -begin - Process.kill(0, minion) - puts "#{minion} is alive!" -rescue Errno::EPERM # changed uid - puts "#{minion} has escaped my control!"; -rescue Errno::ESRCH - puts "#{minion} is deceased."; # or zombied -rescue - puts "Odd; I couldn't check the status of #{minion} : #{$!}" -end - - -# @@PLEAC@@_16.15 -Kernel.trap("QUIT", got_sig_quit) # got_sig_quit = Proc.new { puts "Quit\n" } -trap("PIPE", "got_sig_quit") # def got_sig_pipe ... -trap("INT") { ouch++ } # increment ouch for every SIGINT -#----------------------------- -trap("INT", "IGNORE") # ignore the signal INT -#----------------------------- -trap("STOP", "DEFAULT") # restore default STOP signal handling - - -# @@PLEAC@@_16.16 -# the signal handler -def ding - trap("INT", "ding") - puts "\aEnter your name!" -end - -# prompt for name, overriding SIGINT -def get_name - save = trap("INT", "ding") - - puts "Kindly Stranger, please enter your name: " - name = gets().chomp() - trap("INT", save) - name -end - - -# @@PLEAC@@_16.21 -# implemented thanks to http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/1760 -require 'timeout' - -# we'll do something vastly more useful than cookbook to demonstrate timeouts -begin - timeout(5) { - waitsec = rand(10) - puts "Let's see if a sleep of #{waitsec} seconds is longer than 5 seconds..." - system("sleep #{waitsec}") - } - puts "Timeout didn't occur" -rescue Timeout::Error - puts "Timed out!" -end - - -# @@PLEAC@@_17.1 -# A basic TCP client connection -require 'socket' -begin - t = TCPSocket.new('www.ruby-lang.org', 'www') -rescue - puts "error: #{$!}" -else - # ... do something with the socket - t.print "GET / HTTP/1.0\n\n" - answer = t.gets(nil) - # and terminate the connection when we're done - t.close -end - -# Using the evil low level socket API -require 'socket' -# create a socket -s = Socket.new(Socket::AF_INET, Socket::SOCK_STREAM, 0) -# build the address of the remote machine -sockaddr_server = [Socket::AF_INET, 80, - Socket.gethostbyname('www.ruby-lang.org')[3], - 0, 0].pack("snA4NN") -# connect -begin - s.connect(sockaddr_server) -rescue - puts "error: #{$!}" -else - # ... do something with the socket - s.print "GET / HTTP/1.0\n\n" - # and terminate the connection when we're done - s.close -end - -# TCP connection with management of error (DNS) -require 'socket' -begin - client = TCPSocket.new('does not exists', 'www') -rescue - puts "error: #{$!}" -end - -# TCP connection with a time out -require 'socket' -require 'timeout' -begin - timeout(1) do #the server has one second to answer - client = TCPSocket.new('www.host.com', 'www') - end -rescue - puts "error: #{$!}" -end - - -# @@PLEAC@@_17.12 -require 'socket' - -class Preforker - attr_reader (:child_count) - - def initialize(prefork, max_clients_per_child, port, client_handler) - @prefork = prefork - @max_clients_per_child = max_clients_per_child - @port = port - @child_count = 0 - - @reaper = proc { - trap('CHLD', @reaper) - pid = Process.wait - @child_count -= 1 - } - - @huntsman = proc { - trap('CHLD', 'IGNORE') - trap('INT', 'IGNORE') - Process.kill('INT', 0) - exit - } - - @client_handler=client_handler - end - - def child_handler - trap('INT', 'EXIT') - @client_handler.setUp - # wish: sigprocmask UNblock SIGINT - @max_clients_per_child.times { - client = @server.accept or break - @client_handler.handle_request(client) - client.close - } - @client_handler.tearDown - end - - def make_new_child - # wish: sigprocmask block SIGINT - @child_count += 1 - pid = fork do - child_handler - end - # wish: sigprocmask UNblock SIGINT - end - - def run - @server = TCPserver.open(@port) - trap('CHLD', @reaper) - trap('INT', @huntsman) - loop { - (@prefork - @child_count).times { |i| - make_new_child - } - sleep .1 - } - end -end - -#----------------------------- -#!/usr/bin/ruby - -require 'Preforker' - -class ClientHandler - def setUp - end - - def tearDown - end - - def handle_request(client) - # do stuff - end -end - -server = Preforker.new(1, 100, 3102, ClientHandler.new) -server.run - - -# @@PLEAC@@_18.2 -require 'net/ftp' - -begin - ftp = Net::FTP::new("ftp.host.com") - ftp.login(username,password) - ftp.chdir(directory) - ftp.get(filename) - ftp.put(filename) -rescue Net::FTPError - $stderr.print "FTP failed: " + $! -ensure - ftp.close() if ftp -end - -# A better solution for a local use could be : -Net::FTP::new("ftp.host.com") do |ftp| - ftp.login(username,password) - ftp.chdir(directory) - ftp.get(filename) - ftp.put(filename) -end - -# If you have only one file to get, there is a simple solution : -require 'open-uri' -open("ftp://www.ruby-lang.org/path/filename") do |fh| - # read from filehandle fh -end -#-------------------------------------------- -# to wait a defined time for the connection, -# use the timeout module -require 'timeout' -begin - timeout(30){ - ftp = Net::FTP::new("ftp.host.com") - ftp.debug_mode = true - } -rescue Net::FTPError - $stderr.puts "Couldn't connect." -rescue Timeout::Error - $stderr.puts "Timeout while connecting to server." -end - -begin - ftp.login() -rescue Net::FTPError - $stderr.print "Couldn't authentificate.\n" -end - -begin - ftp.login(username) -rescue Net::FTPError - $stderr.print "Still couldn't authenticate.\n" -end - -begin - ftp.login(username, password) -rescue Net::FTPError - $stderr.print "Couldn't authenticate, even with explicit - username and password.\n" -end - -begin - ftp.login(username, password, account) -rescue Net::FTPError - $stderr.print "No dice. It hates me.\n" -end -#----------------------------- -ftp.put(localfile, remotefile) -#----------------------------- -# Sending data from STDIN is not directly supported -# by the ftp library module. A possible way to do it is to use the -# storlines method directly to send raw commands to the ftp server. -#----------------------------- -ftp.get(remotefile, localfile) -#----------------------------- -ftp.get(remotefile) { |data| puts data } -#----------------------------- -ftp.chdir("/pub/ruby") -print "I'm in the directory ", ftp.pwd(), "\n" -#----------------------------- -ftp.mkdir("/pub/ruby/new_dir") -#----------------------------- -lines = ftp.ls("/pub/ruby/") -# => ["drwxr-xr-x 2 matz users 4096 July 17 1998 1.0", ... ] - -latest = ftp.dir("/pub/ruby/*.tgz").sort.last - -ftp.nlst("/pub/ruby") -# => ["/pub/ruby/1.0", ... ] -#----------------------------- -ftp.quit() - - -# @@PLEAC@@_18.6 -require 'net/telnet' -t = Net::Telnet::new( "Timeout" => 10, - "Prompt" => /%/, - "Host" => host ) -t.login(username, password) -files = t.cmd("ls") -t.print("top") -process_string = t.waitfor(/\d+ processes/) -t.close -#----------------------------- -/[$%#>] \z/n -#----------------------------- -# In case of an error, the telnet module throws an exception. -# For control of the behavior in case of an error, -# you just need to catch the exceptions and do your custom -# error handling. -#----------------------------- -begin - telnet.login(username, password) -rescue TimeoutError - fail "Login failed !\n" -end -#----------------------------- -telnet.waitfor('/--more--/') -#----------------------------- -telnet.waitfor(String => 'greasy smoke', Timeout => 30) - - -# @@PLEAC@@_18.7 -require 'ping' - -puts "#{host} is alive.\n" if Ping.pingecho(host); -#----------------------------- -# the ping module only use TCP ping, not ICMP even if we are root -if Ping.pingecho("kingkong.com") - puts "The giant ape lives!\n"; -else - puts "All hail mighty Gamera, friend of children!\n"; -end - - -# @@PLEAC@@_19.0 -#----------------------------- -# http://www.perl.com/CPAN/ -# http://www.perl.com:8001/bad/mojo.html -# ftp://gatekeeper.dec.com/pub/misc/netlib.tar.Z -# ftp://anonymous@myplace:gatekeeper.dec.com/pub/misc/netlib.tar.Z -# file:///etc/motd -#----------------------------- -# http://mox.perl.com/cgi-bin/program?name=Johann&born=1685 -#----------------------------- -# http://mox.perl.com/cgi-bin/program -#----------------------------- - - -# @@PLEAC@@_19.1 -#!/usr/local/bin/ruby -w -# hiweb - load CGI class to decode information given by web server - -require 'cgi' - -cgi = CGI.new('html3') - -# get a parameter from a form -value = cgi.params['PARAM_NAME'][0] - -# output a document -cgi.out { - cgi.html { - cgi.head { cgi.title { "Howdy there!" } } + - cgi.body { cgi.p { "You typed: " + cgi.tt { - CGI.escapeHTML(value) } } } - } -} - -require 'cgi' -cgi = CGI.new -who = cgi.param["Name"][0] # first param in list -phone = cgi.param["Number"][0] -picks = cgi.param["Choices"] # complete list - -print cgi.header( 'type' => 'text/plain', - 'expires' => Time.now + (3 * 24 * 60 * 60) ) - - -# @@PLEAC@@_19.3 -#!/usr/local/bin/ruby -w -# webwhoami - show web user's id -require 'etc' -print "Content-Type: text/plain\n\n" -print "Running as " + Etc.getpwuid.name + "\n" - -# % ruby -wc cgi-script # just check syntax - -# % ruby -w cgi-script # params from stdin -# (offline mode: enter name=value pairs on standard input) -# name=joe -# number=10 -# ^D - -# % ruby -w cgi-script name=joe number=10 # run with mock form input -# % ruby -d cgi-script name=joe number=10 # ditto, under the debugger - -# POST method script in csh -# % (setenv HTTP_METHOD POST; ruby -w cgi-script name=joe number=10) -# POST method script in sh -# % HTTP_METHOD=POST perl -w cgi-script name=joe number=10 - - -# @@PLEAC@@_19.4 -# ruby has several security levels, the level "1" is similar to perls taint mode. -# It can be switched on by providing the -T command line parameter -# or by setting $SAFE to 1. Setting $SAFE to 2,3 or 4 restricts possible -# harmful operations further. - -#!/usr/bin/ruby -T -$SAFE = 1 -File.open(ARGV[0], "w") -# ruby warns with: -# taint1.rb:2:in `initialize': Insecure operation - initialize (SecurityError) - -$SAFE = 1 -file = ARGV[0] -unless /^([\w.-]+)$/.match(file) - raise "filename #{file} has invalid characters" -end -file = $1 -# In ruby, even the back reference from a regular expression stays tainted. -# you need to explicitly untaint the variable: -file.untaint -File.open(file, "w") - -# Race condition exists like in perl: -unless File.exists(filename) # Wrong because of race condition - File.open(filename, "w") -end - - -# @@PLEAC@@_19.8 -url = "http://pleac.sourceforge.net/pleac_ruby/" -print "Location: #{url}\r\n\r\n" -exit - -#!/usr/bin/ruby -require 'cgi' - -cgi = CGI.new -oreo = CGI::Cookie.new('name' => 'filling', - 'value' => 'vanilla creme', - 'expires' => Time.now + (3 * 30 * 24 * 60 * 60), - 'domain' => '.pleac.sourceforge.net') - -whither = 'http://pleac.sourceforge.net/pleac_ruby/cgiprogramming.html' - -cgi.out('cookie' => oreo, - 'Location' => whither){""} - -#!/usr/bin/ruby -# os_snipe - redirect to a Jargon File entry about current OS -dir = 'http://www.elsewhere.org/jargon/html/entry' - -agent = ENV['HTTP_USER_AGENT'] - -page = case - when agent =~ /Mac/: 'Macintrash.html' - when agent =~ /Win(dows )?NT/: 'evil_and_rude.html' - when agent =~ /Win|MSIE|WebTV/: 'Microsloth_Windows.html' - when agent =~ /Linux/: 'Linux.html' - when agent =~ /HP-UX/: 'HP-SUX.html' - when agent =~ /SunOS/: 'ScumOS.html' - else 'Appendix_B.html' -end - -print "Location: #{dir}/#{page}\n\n" - -require 'cgi' -cgi = CGI.new -cgi.out('status' => '204 No response'){""} -# this produces: -# Status: 204 No response -# Content-Type: text/html -# Content-Length: 0 -# <blank line here> - - -# @@PLEAC@@_19.10 -preference_value = cgi.cookies["preference name"][0] - -packed_cookie = CGI::Cookie.new("name" => "preference name", - "value" => "whatever you'd like", - "expires" => Time.local(Time.now.year + 2, - Time.now.mon, Time.now.day, Time.now.hour, Time.now.min, Time.now.sec) ) - -cgi.header("cookie" => [packed_cookie]) - -#!/usr/local/bin/ruby -w -# ic_cookies - sample CGI script that uses a cookie -require 'cgi' - -cgi = CGI.new('html3') - -cookname = "favorite ice cream" -favorite = cgi.params["flavor"][0] -tasty = cgi.cookies[cookname][0] || 'mint' - -unless favorite - cgi.out { - cgi.html { - cgi.head { cgi.title { "Ice Cookies" } } + - cgi.body { - cgi.h1 { "Hello Ice Cream" } + - cgi.hr + - cgi.form { - cgi.p { "Please select a flavor: " + - cgi.text_field("flavor", tasty ) } - } + - cgi.hr - } - } - } -else - cookie = CGI::Cookie.new( "name" => cookname, - "value" => favorite, - "expires" => Time.local(Time.now.year + 2, -Time.now.mon, Time.now.day, Time.now.hour, Time.now.min, Time.now.sec) ) - cgi.out("cookie" => [cookie]) { - cgi.html { - cgi.head { cgi.title { "Ice Cookies" } } + - cgi.body { - cgi.h1 { "Hello Ice Cream" } + - cgi.p { "You chose as your favorite flavor `#{favorite}'." } - } - } - } -end - - -# @@PLEAC@@_20.9 -def templatefile(filename, fillings) - aFile = File.new(filename, "r") - text = aFile.read() - aFile.close() - pattern = Regexp.new('%%(.*?)%%') - text.gsub!(pattern) { - fillings[$1] || "" - } - text -end - -fields = { - 'username' => whats_his_name, - 'count' => login_count, - 'total' => minutes_used -} -puts templatefile('simple.template', fields) - -# @@INCOMPLETE@@ -# An example using databases is missing - - |