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How to make TreeParser in ANTLR3?

I learn parsing language for fun ...

I created an ANTLR grammar, which, I believe, will correspond to a simple language that I hope to implement. It will have the following syntax:

<FunctionName> ( <OptionalArguments>+) {
     <OptionalChildFunctions>+
 }

Actual example:

ForEach(in:[1,2,3,4,5] as:"nextNumber") {
   Print(message:{nextNumber})
}

I believe that I have the correct grammar to fit this design, and now I'm trying to build an abstract syntax tree for the language.

First, I must admit that I'm not quite sure HOW this tree should look. Secondly, I have a complete loss of how to do this in my Antlr grammar ... I tried without much success for hours.

This is the real idea I'm coming with for the tree - please come with me! :)

                   FunctionName
                  /          \
           Attributes         \
               / \          /  \ 
            ID    /\    ChildFunctions
           / \   ID etc
          /   \
  Attribute  AttributeValue
        Type

This is my current Antlr grammar file:

grammar Test;

options {output=AST;ASTLabelType=CommonTree;}

program : function ;
function : ID (OPEN_BRACKET (attribute (COMMA? attribute)*)? CLOSE_BRACKET)? (OPEN_BRACE function* CLOSE_BRACE)?;

attribute : ID COLON datatype;

datatype : NUMBER | STRING | BOOLEAN | array | lookup ;
array  :  OPEN_BOX (datatype (COMMA datatype)* )? CLOSE_BOX ;
lookup  : OPEN_BRACE (ID (PERIOD ID)*) CLOSE_BRACE;

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 : ':' ;
COMMA : ',' ;
PERIOD  :  '.' ;

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'|'\"'|'\''|'\\')
    ;

/ . , , , : (

+4
1

1 , , . - , .

. - antlr.org.

ANTLRWorks, , AST. , .

EDIT/ :

, :

  • ANTLRWorks . AST . , , IDE , .

  • - !, node , ^, ANTLR - root node. , AST. , . , ( AST), . , ! . :

    function: ID (OPEN_BRACKET! (attribute (COMMA!? attribute)*)? CLOSE_BRACKET!)? (OPEN_BRACE! function* CLOSE_BRACE!)?;

  • AST ANTLRWorks . .

  • , node. , , ID node, ^ ID ANTLRWorks.

, , :

program : function ;
function : ID^ (OPEN_BRACKET! attributeList? CLOSE_BRACKET!)? (OPEN_BRACE! function* CLOSE_BRACE!)?;
attributeList:  (attribute (COMMA!? attribute)*);
attribute : ID COLON! datatype;
datatype : NUMBER | STRING | BOOLEAN | array | lookup ;
array  :  OPEN_BOX! (datatype^ (COMMA! datatype)* )? CLOSE_BOX!;
lookup  : OPEN_BRACE! (ID (PERIOD! ID)*) CLOSE_BRACE!;

.

+9

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