Add compiler from rosettacode.org; fix bug in ParserElement.runTests that interpreted newlines in quotes as test delimiters

1 files changed, 278 insertions, 0 deletions

diff --git a/examples/rosettacode.py b/examples/rosettacode.py
new file mode 100644
index 0000000..07ed7fa
--- /dev/null
+++ b/examples/rosettacode.py
@@ -0,0 +1,278 @@
+#
+# rosettacode.py
+#
+# parser for language used by rosettacode.org (http://rosettacode.org/wiki/Compiler/syntax_analyzer)
+#
+# Copyright Paul McGuire, 2019
+#
+BNF = """
+    stmt_list           =   {stmt} ;
+ 
+    stmt                =   ';'
+                          | Identifier '=' expr ';'
+                          | 'while' paren_expr stmt
+                          | 'if' paren_expr stmt ['else' stmt]
+                          | 'print' '(' prt_list ')' ';'
+                          | 'putc' paren_expr ';'
+                          | '{' stmt_list '}'
+                          ;
+ 
+    paren_expr          =   '(' expr ')' ;
+ 
+    prt_list            =   string | expr {',' String | expr} ;
+ 
+    expr                =   and_expr            {'||' and_expr} ;
+    and_expr            =   equality_expr       {'&&' equality_expr} ;
+    equality_expr       =   relational_expr     [('==' | '!=') relational_expr] ;
+    relational_expr     =   addition_expr       [('<' | '<=' | '>' | '>=') addition_expr] ;
+    addition_expr       =   multiplication_expr {('+' | '-') multiplication_expr} ;
+    multiplication_expr =   primary             {('*' | '/' | '%') primary } ;
+    primary             =   Identifier
+                          | Integer
+                          | '(' expr ')'
+                          | ('+' | '-' | '!') primary
+                          ;
+"""
+
+import pyparsing as pp
+pp.ParserElement.enablePackrat()
+
+LBRACE, RBRACE, LPAR, RPAR, SEMI = map(pp.Suppress, "{}();")
+EQ = pp.Literal('=')
+
+keywords = (WHILE, IF, PRINT, PUTC, ELSE) = map(pp.Keyword, "while if print putc else".split())
+identifier = ~(pp.MatchFirst(keywords)) + pp.pyparsing_common.identifier
+integer = pp.pyparsing_common.integer
+string =  pp.QuotedString('"', convertWhitespaceEscapes=False).setName("quoted string")
+char = pp.Regex(r"'\\?.'")
+
+expr = pp.infixNotation(identifier | integer | char,
+                        [
+                            (pp.oneOf("+ - !"), 1, pp.opAssoc.RIGHT,),
+                            (pp.oneOf("* / %"), 2, pp.opAssoc.LEFT, ),
+                            (pp.oneOf("+ -"), 2, pp.opAssoc.LEFT,),
+                            (pp.oneOf("< <= > >="), 2, pp.opAssoc.LEFT,),
+                            (pp.oneOf("== !="), 2, pp.opAssoc.LEFT,),
+                            (pp.oneOf("&&"), 2, pp.opAssoc.LEFT,),
+                            (pp.oneOf("||"), 2, pp.opAssoc.LEFT,),
+                        ])
+
+prt_list = pp.Group(pp.delimitedList(string | expr))
+paren_expr = pp.Group(LPAR + expr + RPAR)
+
+stmt = pp.Forward()
+assignment_stmt = pp.Group(identifier + EQ + expr + SEMI)
+while_stmt = pp.Group(WHILE - paren_expr + stmt)
+if_stmt = pp.Group(IF - paren_expr + stmt + pp.Optional(ELSE + stmt))
+print_stmt = pp.Group(PRINT - pp.Group(LPAR + prt_list + RPAR) + SEMI)
+putc_stmt = pp.Group(PUTC - paren_expr + SEMI)
+stmt_list = pp.Group(LBRACE + pp.ZeroOrMore(stmt) + RBRACE)
+stmt <<= (pp.Group(SEMI)
+          | assignment_stmt
+          | while_stmt
+          | if_stmt
+          | print_stmt
+          | putc_stmt
+          | stmt_list
+          ).setName("statement")
+
+code = pp.ZeroOrMore(stmt)
+code.ignore(pp.cppStyleComment)
+
+
+tests = [
+    r'''
+        count = 1;
+        while (count < 10) {
+            print("count is: ", count, "\n");
+            count = count + 1;
+        }
+    ''',
+    r'''
+        /*
+         Simple prime number generator
+         */
+        count = 1;
+        n = 1;
+        limit = 100;
+        while (n < limit) {
+            k=3;
+            p=1;
+            n=n+2;
+            while ((k*k<=n) && (p)) {
+                p=n/k*k!=n;
+                k=k+2;
+            }
+            if (p) {
+                print(n, " is prime\n");
+                count = count + 1;
+            }
+        }
+        print("Total primes found: ", count, "\n");
+    ''',
+    r'''
+        /*
+          Hello world
+         */
+        print("Hello, World!\n");    
+    ''',
+    r'''
+        /*
+          Show Ident and Integers
+         */
+        phoenix_number = 142857;
+        print(phoenix_number, "\n");
+    ''',
+    r'''
+        /*** test printing, embedded \n and comments with lots of '*' ***/
+        print(42);
+        print("\nHello World\nGood Bye\nok\n");
+        print("Print a slash n - \\n.\n");
+    ''',
+    r'''
+        /* 100 Doors */
+        i = 1;
+        while (i * i <= 100) {
+            print("door ", i * i, " is open\n");
+            i = i + 1;
+        }
+    ''',
+    r'''
+        a = (-1 * ((-1 * (5 * 15)) / 10));
+        print(a, "\n");
+        b = -a;
+        print(b, "\n");
+        print(-b, "\n");
+        print(-(1), "\n");
+    ''',
+    r'''
+        print(---------------------------------+++5, "\n");
+        print(((((((((3 + 2) * ((((((2))))))))))))), "\n");
+         
+        if (1) { if (1) { if (1) { if (1) { if (1) { print(15, "\n"); } } } } }
+    ''',
+    r'''
+        /* Compute the gcd of 1071, 1029:  21 */
+         
+        a = 1071;
+        b = 1029;
+         
+        while (b != 0) {
+            new_a = b;
+            b     = a % b;
+            a     = new_a;
+        }
+        print(a);
+    ''',
+    r'''
+        /* 12 factorial is 479001600 */
+         
+        n = 12;
+        result = 1;
+        i = 1;
+        while (i <= n) {
+            result = result * i;
+            i = i + 1;
+        }
+        print(result);
+    ''',
+    r'''
+        /* fibonacci of 44 is 701408733 */
+         
+        n = 44;
+        i = 1;
+        a = 0;
+        b = 1;
+        while (i < n) {
+            w = a + b;
+            a = b;
+            b = w;
+            i = i + 1;
+        }
+        print(w, "\n");
+    ''',
+    r'''
+        /* FizzBuzz */
+        i = 1;
+        while (i <= 100) {
+            if (!(i % 15))
+                print("FizzBuzz");
+            else if (!(i % 3))
+                print("Fizz");
+            else if (!(i % 5))
+                print("Buzz");
+            else
+                print(i);
+         
+            print("\n");
+            i = i + 1;
+        }
+    ''',
+    r'''
+        /* 99 bottles */
+        bottles = 99;
+        while (bottles > 0) {
+            print(bottles, " bottles of beer on the wall\n");
+            print(bottles, " bottles of beer\n");
+            print("Take one down, pass it around\n");
+            bottles = bottles - 1;
+            print(bottles, " bottles of beer on the wall\n\n");
+        }
+    ''',
+    r'''
+         {
+        /*
+         This is an integer ascii Mandelbrot generator
+         */
+            left_edge   = -420;
+            right_edge  =  300;
+            top_edge    =  300;
+            bottom_edge = -300;
+            x_step      =    7;
+            y_step      =   15;
+         
+            max_iter    =  200;
+         
+            y0 = top_edge;
+            while (y0 > bottom_edge) {
+                x0 = left_edge;
+                while (x0 < right_edge) {
+                    y = 0;
+                    x = 0;
+                    the_char = ' ';
+                    i = 0;
+                    while (i < max_iter) {
+                        x_x = (x * x) / 200;
+                        y_y = (y * y) / 200;
+                        if (x_x + y_y > 800 ) {
+                            the_char = '0' + i;
+                            if (i > 9) {
+                                the_char = '@';
+                            }
+                            i = max_iter;
+                        }
+                        y = x * y / 100 + y0;
+                        x = x_x - y_y + x0;
+                        i = i + 1;
+                    }
+                    putc(the_char);
+                    x0 = x0 + x_step;
+                }
+                putc('\n');
+                y0 = y0 - y_step;
+            }
+        }
+    ''',
+]
+
+import sys
+sys.setrecursionlimit(2000)
+
+for test in tests:
+    try:
+        results = code.parseString(test)
+    except pp.ParseException as pe:
+        pp.ParseException.explain(pe)
+    else:
+        results.pprint()
+    print()