---input---
CMAKE_MINIMUM_REQUIRED(VERSION 2.6 FATAL_ERROR)

SET( SOURCES back.c io.c main.c )
SET( PATH $ENV{PATH} )
MESSAGE( ${SOURCES}   )      # three arguments, prints "back.cio.cmain.c"
MESSAGE( "${SOURCES}" )      # one argument,    prints "back.c;io.c;main.c"
MESSAGE( "" )                # one argument,    prints "" an empty line
MESSAGE( "${EMPTY_STRING}" ) # one argument,    prints "" an empty line
MESSAGE( ${EMPTY_STRING} )   # zero arguments,  causes CMake Error
                             # "MESSAGE called with incorrect number of arguments"
MESSAGE( \\\"\ \(\)\#\$\^ ) # this message contains literal characters

MESSAGE( "This is practice." )  # prints "This is practice."
MESSAGE( "This;is;practice." )  # prints "This;is;practice."
MESSAGE( "Hi. ) MESSAGE( x )" ) # prints "Hi. ) MESSAGE( x )"

MESSAGE( "Welc"ome ) # rule 1
MESSAGE( Welc"ome" ) # rule 3
MESSAGE( Welc"ome)" ) # rule 2
MESSAGE( ""Thanks ) # rule 1
MESSAGE( Thanks"" ) # rule 3

SET( x y A B C )              # stores "y;A;B;C" in x (without quote)
SET( ${x} )                   # => SET( y;A;B;C ) => SET( y A B C)
MESSAGE( ${y} )               # prints "ABC" to stdout (without quotes)
SET( y x )                    # stores "x" in y (without quotes)
SET( ${y} y = x )             # => SET( x y )
MESSAGE( "\${x} = '${x}'" )   # prints "${x} = 'y;=;x'" to stdout (without quotes)
SET( y ${x} )                 # => SET( y y = x ) => stores "y;=;x" in y (without quotes)
MESSAGE( ${y} )               # prints "y=x" to stdout (without quotes)

SET( x a b c   ) # stores "a;b;c" in x      (without quotes)
SET( y "a b c" ) # stores "a b c" in y      (without quotes)
MESSAGE( a b c ) # prints "abc"   to stdout (without quotes)
MESSAGE( ${x} )  # prints "abc"   to stdout (without quotes)
MESSAGE("${x}")  # prints "a;b;c" to stdout (without quotes)
MESSAGE( ${y} )  # prints "a b c" to stdout (without quotes)
MESSAGE("${y}")  # prints "a b c" to stdout (without quotes)

# This is a comment.
COMMAND( arguments go here )
ANOTHER_COMMAND() # this command has no arguments
YET_ANOTHER_COMMAND( these
  arguments are spread         # another comment
  over several lines )

---tokens---
'CMAKE_MINIMUM_REQUIRED' Name.Builtin
'('           Punctuation
'VERSION'     Literal.String
' '           Text
'2.6'         Literal.String
' '           Text
'FATAL_ERROR' Literal.String
')'           Punctuation
'\n'          Text

'\n'          Text

'SET'         Name.Builtin
'('           Punctuation
' '           Text
'SOURCES'     Literal.String
' '           Text
'back.c'      Literal.String
' '           Text
'io.c'        Literal.String
' '           Text
'main.c'      Literal.String
' '           Text
')'           Punctuation
'\n'          Text

'SET'         Name.Builtin
'('           Punctuation
' '           Text
'PATH'        Literal.String
' '           Text
'$ENV{'       Operator
'PATH'        Name.Variable
'}'           Operator
' '           Text
')'           Punctuation
'\n'          Text

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'${'          Operator
'SOURCES'     Name.Variable
'}'           Operator
'   '         Text
')'           Punctuation
'      '      Text
'# three arguments, prints "back.cio.cmain.c"\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'"${SOURCES}"' Literal.String.Double
' '           Text
')'           Punctuation
'      '      Text
'# one argument,    prints "back.c;io.c;main.c"\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'""'          Literal.String.Double
' '           Text
')'           Punctuation
'                ' Text
'# one argument,    prints "" an empty line\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'"${EMPTY_STRING}"' Literal.String.Double
' '           Text
')'           Punctuation
' '           Text
'# one argument,    prints "" an empty line\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'${'          Operator
'EMPTY_STRING' Name.Variable
'}'           Operator
' '           Text
')'           Punctuation
'   '         Text
'# zero arguments,  causes CMake Error\n' Comment

'                             ' Text
'# "MESSAGE called with incorrect number of arguments"\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'\\\\\\"\\'   Literal.String
' '           Text
'\\(\\)\\#\\$\\^' Literal.String
' '           Text
')'           Punctuation
' '           Text
'# this message contains literal characters\n' Comment

'\n'          Text

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'"This is practice."' Literal.String.Double
' '           Text
')'           Punctuation
'  '          Text
'# prints "This is practice."\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'"This;is;practice."' Literal.String.Double
' '           Text
')'           Punctuation
'  '          Text
'# prints "This;is;practice."\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'"Hi. ) MESSAGE( x )"' Literal.String.Double
' '           Text
')'           Punctuation
' '           Text
'# prints "Hi. ) MESSAGE( x )"\n' Comment

'\n'          Text

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'"Welc"'      Literal.String.Double
'ome'         Literal.String
' '           Text
')'           Punctuation
' '           Text
'# rule 1\n'  Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'Welc'        Literal.String
'"ome"'       Literal.String.Double
' '           Text
')'           Punctuation
' '           Text
'# rule 3\n'  Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'Welc'        Literal.String
'"ome)"'      Literal.String.Double
' '           Text
')'           Punctuation
' '           Text
'# rule 2\n'  Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'""'          Literal.String.Double
'Thanks'      Literal.String
' '           Text
')'           Punctuation
' '           Text
'# rule 1\n'  Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'Thanks'      Literal.String
'""'          Literal.String.Double
' '           Text
')'           Punctuation
' '           Text
'# rule 3\n'  Comment

'\n'          Text

'SET'         Name.Builtin
'('           Punctuation
' '           Text
'x'           Literal.String
' '           Text
'y'           Literal.String
' '           Text
'A'           Literal.String
' '           Text
'B'           Literal.String
' '           Text
'C'           Literal.String
' '           Text
')'           Punctuation
'              ' Text
'# stores "y;A;B;C" in x (without quote)\n' Comment

'SET'         Name.Builtin
'('           Punctuation
' '           Text
'${'          Operator
'x'           Name.Variable
'}'           Operator
' '           Text
')'           Punctuation
'                   ' Text
'# => SET( y;A;B;C ) => SET( y A B C)\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'${'          Operator
'y'           Name.Variable
'}'           Operator
' '           Text
')'           Punctuation
'               ' Text
'# prints "ABC" to stdout (without quotes)\n' Comment

'SET'         Name.Builtin
'('           Punctuation
' '           Text
'y'           Literal.String
' '           Text
'x'           Literal.String
' '           Text
')'           Punctuation
'                    ' Text
'# stores "x" in y (without quotes)\n' Comment

'SET'         Name.Builtin
'('           Punctuation
' '           Text
'${'          Operator
'y'           Name.Variable
'}'           Operator
' '           Text
'y'           Literal.String
' '           Text
'='           Literal.String
' '           Text
'x'           Literal.String
' '           Text
')'           Punctuation
'             ' Text
'# => SET( x y )\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'"\\${x} = \'${x}\'"' Literal.String.Double
' '           Text
')'           Punctuation
'   '         Text
'# prints "${x} = \'y;=;x\'" to stdout (without quotes)\n' Comment

'SET'         Name.Builtin
'('           Punctuation
' '           Text
'y'           Literal.String
' '           Text
'${'          Operator
'x'           Name.Variable
'}'           Operator
' '           Text
')'           Punctuation
'                 ' Text
'# => SET( y y = x ) => stores "y;=;x" in y (without quotes)\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'${'          Operator
'y'           Name.Variable
'}'           Operator
' '           Text
')'           Punctuation
'               ' Text
'# prints "y=x" to stdout (without quotes)\n' Comment

'\n'          Text

'SET'         Name.Builtin
'('           Punctuation
' '           Text
'x'           Literal.String
' '           Text
'a'           Literal.String
' '           Text
'b'           Literal.String
' '           Text
'c'           Literal.String
'   '         Text
')'           Punctuation
' '           Text
'# stores "a;b;c" in x      (without quotes)\n' Comment

'SET'         Name.Builtin
'('           Punctuation
' '           Text
'y'           Literal.String
' '           Text
'"a b c"'     Literal.String.Double
' '           Text
')'           Punctuation
' '           Text
'# stores "a b c" in y      (without quotes)\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'a'           Literal.String
' '           Text
'b'           Literal.String
' '           Text
'c'           Literal.String
' '           Text
')'           Punctuation
' '           Text
'# prints "abc"   to stdout (without quotes)\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'${'          Operator
'x'           Name.Variable
'}'           Operator
' '           Text
')'           Punctuation
'  '          Text
'# prints "abc"   to stdout (without quotes)\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
'"${x}"'      Literal.String.Double
')'           Punctuation
'  '          Text
'# prints "a;b;c" to stdout (without quotes)\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
' '           Text
'${'          Operator
'y'           Name.Variable
'}'           Operator
' '           Text
')'           Punctuation
'  '          Text
'# prints "a b c" to stdout (without quotes)\n' Comment

'MESSAGE'     Name.Builtin
'('           Punctuation
'"${y}"'      Literal.String.Double
')'           Punctuation
'  '          Text
'# prints "a b c" to stdout (without quotes)\n' Comment

'\n'          Text

'# This is a comment.\n' Comment

'COMMAND'     Name.Builtin
'('           Punctuation
' '           Text
'arguments'   Literal.String
' '           Text
'go'          Literal.String
' '           Text
'here'        Literal.String
' '           Text
')'           Punctuation
'\n'          Text

'ANOTHER_COMMAND' Name.Builtin
'('           Punctuation
')'           Punctuation
' '           Text
'# this command has no arguments\n' Comment

'YET_ANOTHER_COMMAND' Name.Builtin
'('           Punctuation
' '           Text
'these'       Literal.String
'\n'          Text

'  '          Text
'arguments'   Literal.String
' '           Text
'are'         Literal.String
' '           Text
'spread'      Literal.String
'         '   Text
'# another comment\n' Comment

'  '          Text
'over'        Literal.String
' '           Text
'several'     Literal.String
' '           Text
'lines'       Literal.String
' '           Text
')'           Punctuation
'\n'          Text