Antrl3 conditional tree rewrites
Stackoverflow.
Continuing on my journey into Antlr (Previous questions may provide additional clues on what I'm trying to achieve! Q1 - How do I make a tree parser and Q2 - Solving LL recursion problem) I've hit yet another roadblock I cannot flathom.
Basically (I believe) the expression
rule in my grammar needs to either create a new root node depending on the number of datatype
s it has matched. I have put together an example to try best describe what I mean:
Given the following input:
ComplexFunction(id="Test" args:[1, 25 + 9 + 8, true, [1,2,3]])
I get this tree:
http://img25.imageshack.us/img25/2273/treeka.png
For reference - The first element in the "args" array as been correctly parsed. Whereas the 2nd element in the array "args" '25 + 9 + 8' has not. It appears to only match the last 2 parts of the expression (9 + 8).
I'm trying to get the 2nd element of the array to be an EXPRESSION
node, with the 3 children 25, 9, and 8).
I'm honestly stuck and need your help (Again). Thanks for your time :)
For reference, here is my grammar:
grammar Test;
options {output=AST;ASTLabelType=CommonTree;}
tokens {FUNCTION; NAME; ATTRIBUTES; ATTRIBUTE; VALUE; CHILDREN; EXPRESSION;}
program : function ;
function : ID (OPEN_BRACKET (attribute (COMMA? attribute)*)? CLOSE_BRACKET)? (OPEN_BRACE function* CLOSE_BRACE)? SEMICOLON? -> ^(FUNCTION ^(NAME ID) ^(ATTRIBUTES attribute*) ^(CHILDREN function*)) ;
attribute : ID (COLON | EQUALS) expression -> ^(ATTRIBUTE ^(NAME ID) ^(VALUE expression));
expression : datatype (PLUS datatype)* -> datatype ^(EXPRESSION datatype+)?;
datatype : ID -> ^(STRING["ID"] ID)
| NUMBER -> ^(STRING["NUMBER"] NUMBER)
| STRING -> ^(STRING["STRING"] STRING)
| BOOLEAN -> ^(STRING["BOOLEAN"] BOOLEAN)
| array -> ^(STRING["ARRAY"] array)
| lookup -> ^(STRING["LOOKUP"] lookup) ;
array : OPEN_BOX (expression (COMMA expression)*)? CLOSE_BOX -> expression* ;
lookup : OPEN_BRACE (ID (PERIOD ID)*) CLOSE_BRACE -> ID* ;
NUMBER
: ('+' | '-')? (INTEGER | FLOAT)
;
STRING
: '"' ( ESC_SEQ | ~('\\'|'"') )* '"'
;
BOOLEAN
: 'true' | 'TRUE' | 'false' | 'FALSE'
;
ID 开发者_JAVA技巧 : (LETTER|'_') (LETTER | INTEGER |'_')*
;
COMMENT
: '//' ~('\n'|'\r')* '\r'? '\n' {$channel=HIDDEN;}
| '/*' ( options {greedy=false;} : . )* '*/' {$channel=HIDDEN;}
;
WHITESPACE : (' ' | '\t' | '\r' | '\n') {$channel=HIDDEN;} ;
COLON : ':' ;
SEMICOLON : ';' ;
COMMA : ',' ;
PERIOD : '.' ;
PLUS : '+' ;
EQUALS : '=' ;
OPEN_BRACKET : '(' ;
CLOSE_BRACKET : ')' ;
OPEN_BRACE : '{' ;
CLOSE_BRACE : '}' ;
OPEN_BOX : '[' ;
CLOSE_BOX : ']' ;
fragment
LETTER
: 'a'..'z' | 'A'..'Z'
;
fragment
INTEGER
: '0'..'9'+
;
fragment
FLOAT
: INTEGER+ '.' INTEGER*
;
fragment
ESC_SEQ
: '\\' ('b'|'t'|'n'|'f'|'r'|'\"'|'\''|'\\')
;
Haha! I think I got it! If anyone else has a similar problem take a look at my new grammar:
grammar Test;
options {output=AST;ASTLabelType=CommonTree;}
tokens {FUNCTION; ATTRIBUTES; ATTRIBUTE; VALUE; CHILDREN; EXPRESSION;}
@parser::members { int dataTypeCount = 0; }
program : function ;
function : ID (OPEN_BRACKET (attribute (COMMA? attribute)*)? CLOSE_BRACKET)? (OPEN_BRACE function* CLOSE_BRACE)? SEMICOLON? -> ^(FUNCTION ^(ID["ID"] ID) ^(ATTRIBUTES attribute*) ^(CHILDREN function*)) ;
attribute : ID (COLON | EQUALS) expression -> ^(ATTRIBUTE ^(ID["ID"] ID) ^(VALUE expression));
expression : datatype {dataTypeCount = 1;} (PLUS datatype {dataTypeCount++;})*
-> {dataTypeCount == 1}? datatype*
-> ^(EXPRESSION datatype*) ;
datatype : ID -> ^(STRING["ID"] ID)
| NUMBER -> ^(STRING["NUMBER"] NUMBER)
| STRING -> ^(STRING["STRING"] STRING)
| BOOLEAN -> ^(STRING["BOOLEAN"] BOOLEAN)
| array -> ^(STRING["ARRAY"] array)
| lookup -> ^(STRING["LOOKUP"] lookup) ;
array : OPEN_BOX (expression (COMMA expression)*)? CLOSE_BOX -> expression* ;
lookup : OPEN_BRACE (ID (PERIOD ID)*) CLOSE_BRACE -> ID* ;
NUMBER
: ('+' | '-')? (INTEGER | FLOAT)
;
STRING
: '"' ( ESC_SEQ | ~('\\'|'"') )* '"'
;
BOOLEAN
: 'true' | 'TRUE' | 'false' | 'FALSE'
;
ID : (LETTER|'_') (LETTER | INTEGER |'_')*
;
COMMENT
: '//' ~('\n'|'\r')* '\r'? '\n' {$channel=HIDDEN;}
| '/*' ( options {greedy=false;} : . )* '*/' {$channel=HIDDEN;}
;
WHITESPACE : (' ' | '\t' | '\r' | '\n') {$channel=HIDDEN;} ;
COLON : ':' ;
SEMICOLON : ';' ;
COMMA : ',' ;
PERIOD : '.' ;
PLUS : '+' ;
EQUALS : '=' ;
OPEN_BRACKET : '(' ;
CLOSE_BRACKET : ')' ;
OPEN_BRACE : '{' ;
CLOSE_BRACE : '}' ;
OPEN_BOX : '[' ;
CLOSE_BOX : ']' ;
fragment
LETTER
: 'a'..'z' | 'A'..'Z'
;
fragment
INTEGER
: '0'..'9'+
;
fragment
FLOAT
: INTEGER+ '.' INTEGER*
;
fragment
ESC_SEQ
: '\\' ('b'|'t'|'n'|'f'|'r'|'\"'|'\''|'\\')
;
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