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| grammar t017parser;
|
| options {
| language = Python;
| }
|
| program
| : declaration+
| ;
|
| declaration
| : variable
| | functionHeader ';'
| | functionHeader block
| ;
|
| variable
| : type declarator ';'
| ;
|
| declarator
| : ID
| ;
|
| functionHeader
| : type ID '(' ( formalParameter ( ',' formalParameter )* )? ')'
| ;
|
| formalParameter
| : type declarator
| ;
|
| type
| : 'int'
| | 'char'
| | 'void'
| | ID
| ;
|
| block
| : '{'
| variable*
| stat*
| '}'
| ;
|
| stat: forStat
| | expr ';'
| | block
| | assignStat ';'
| | ';'
| ;
|
| forStat
| : 'for' '(' assignStat ';' expr ';' assignStat ')' block
| ;
|
| assignStat
| : ID '=' expr
| ;
|
| expr: condExpr
| ;
|
| condExpr
| : aexpr ( ('==' | '<') aexpr )?
| ;
|
| aexpr
| : atom ( '+' atom )*
| ;
|
| atom
| : ID
| | INT
| | '(' expr ')'
| ;
|
| ID : ('a'..'z'|'A'..'Z'|'_') ('a'..'z'|'A'..'Z'|'0'..'9'|'_')*
| ;
|
| INT : ('0'..'9')+
| ;
|
| WS : ( ' '
| | '\t'
| | '\r'
| | '\n'
| )+
| {$channel=HIDDEN}
| ;
|
|
