Tk Library Source Code

Artifact f598da11baf09ad875b52556b45bf4662917eed5:

Attachment "EmuQL.peg" to ticket [3064747fff] added by dargosch 2010-09-12 19:38:00.

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PEG EmuQL (expression) 
	expression <- unionexpression / dominanceexpressionR / dominanceexpression / sequentialexpressionL / sequentialexpressionR /sequenceexpression / functionexpression /labeltypeexpression  ;
	subexpression <-  functionexpression / labeltypeexpression / ('[' expression ']') ;
	labeltypeexpression <- (WHITESPACE labeltype WHITESPACE stringcompareoperator WHITESPACE labelsequence WHITESPACE) ;
#/ (WHITESPACE labeltype WHITESPACE);

#Dominance expressions
#Default is left part returned, so this is the default match
	dominanceexpression <- WHITESPACE (TARGETMARK)* WHITESPACE subexpression WHITESPACE dominanceoperator WHITESPACE subexpression WHITESPACE ;
	dominanceexpressionR <- WHITESPACE subexpression WHITESPACE dominanceoperator WHITESPACE TARGETMARK WHITESPACE subexpression WHITESPACE ;

#Sequences
#The whole sequence
	sequenceexpression <- WHITESPACE subexpression WHITESPACE sequenceoperator WHITESPACE subexpression WHITESPACE ;
#Return part marked
	sequentialexpressionL <- WHITESPACE TARGETMARK WHITESPACE subexpression WHITESPACE sequenceoperator WHITESPACE subexpression WHITESPACE ;
	sequentialexpressionR <- WHITESPACE subexpression WHITESPACE sequenceoperator WHITESPACE TARGETMARK WHITESPACE subexpression WHITESPACE ;

#Joined expressions
	unionexpression <- subexpression WHITESPACE '&' WHITESPACE subexpression WHITESPACE (ANDOPERATOR WHITESPACE subexpression)* ;

#Function calls
	functionexpression <- WHITESPACE function '(' WHITESPACE labeltype WHITESPACE ',' WHITESPACE labeltype WHITESPACE ')' WHITESPACE numbercompareoperator WHITESPACE number WHITESPACE;

#Basic components
	function <- 'Start' / 'Mid' / 'End'  / 'Num' / 'Position';
	labeltype <- <alnum>+ ;
	number <- (<digit>/<ddigit>)+;
	labelsequence <- label (OROPERATOR label)*;
	label <- (WHITESPACE STRINGMARK STRINGMARK WHITESPACE)  / (WHITESPACE STRINGMARK  (!(STRINGMARK (OROPERATOR/EOS)) unicodestring)*  STRINGMARK WHITESPACE) / (WHITESPACE  asciistring  WHITESPACE) ; 
	unicodestring <- "\\" [nrt'"\[\]\\] / "\\" [0-2][0-7][0-7] / "\\" [0-7][0-7]? / "\\" 'u' HexDigit (HexDigit (HexDigit HexDigit?)?)? /  !"\\" .   ;
	asciistring <- <alnum>+;
	sequenceoperator <- '->' / '-->' / namedsequenceoperator ;
	namedsequenceoperator <- '-' labeltype '->';
	stringcompareoperator <- '=' / '==' / '!=' / '~' / '~~' / '!~' / '!~~';
	numbercompareoperator <- '=' / '==' / '!=' / '<' / '>' / '<=' / '>=';
	dominanceoperator <- '^' / '~^';
void:	OROPERATOR <- '|' ;
void:	ANDOPERATOR <- '&' ;  
void:   WHITESPACE <- (" " / "\t" / "\r" / "\n"   )* ;
void:	FWHITESPACE <- (" " / "\t" / "\r" / "\n"  )+;
void:	TARGETMARK <- '#';
void:	STRINGMARK <- "'" ;
void:   EOL             <- "\n\r" / "\n" / "\r" ;
void: 	EOS <- !unicodestring;
END ;