// name must match file name
grammar WAE;

// Grammar rules

waeStart returns [WAENode value] : 
    w=wae SEMI { $value = $w.value; };

wae returns [WAENode value] : 
    n=NUMBER 
  { WAENode n = new WAENode();
    n.setNodeType("num");
    n.setValue(Double.parseDouble($n.text));
    $value = n;
  }
  | LBRACE PLUS w1=wae w2=wae RBRACE
  { WAENode n = new WAENode();
    n.setNodeType("plus");
    n.setChild1($w1.value);
    n.setChild2($w2.value);
    $value = n;
  }
  | LBRACE MINUS w1=wae w2=wae RBRACE
  { WAENode n = new WAENode();
    n.setNodeType("minus");
    n.setChild1($w1.value);
    n.setChild2($w2.value);
    $value = n;
  }
  | LBRACE TIMES w1=wae w2=wae RBRACE
  { WAENode n = new WAENode();
    n.setNodeType("multiply");
    n.setChild1($w1.value);
    n.setChild2($w2.value);
    $value = n;
  }
  | LBRACE DIV w1=wae w2=wae RBRACE
  { WAENode n = new WAENode();
    n.setNodeType("divide");
    n.setChild1($w1.value);
    n.setChild2($w2.value);
    $value = n;
  }
  | LBRACE IF w1=wae w2=wae w3=wae RBRACE
  { WAENode n = new WAENode();
    n.setNodeType("if");
    n.setChild1($w1.value);
    n.setChild2($w2.value);
    n.setChild3($w3.value);
    $value = n;
  }
;

// Lexer rules
// fragments are not tokens
//fragment VALID_ID_START : ('a'..'z') | ('A'..'Z') | '_';
//fragment VALID_ID_CHAR : VALID_ID_START | ('0'..'9');
fragment I          : ('I'|'i') ;
fragment F          : ('F'|'f') ;
//tokens
NUMBER : ('0'..'9')+;
LBRACE : '{';
RBRACE : '}';
SEMI : ';';
PLUS : '+';
MINUS : '-';
TIMES : '*';
DIV : '/';
IF : I F;
//ID : VALID_ID_START VALID_ID_CHAR*;
//White Space
WS : [ \r\n\t]+ -> skip;