// Test Grammar "G"
ometa G 
{
  digit    = '0' | '1' | '2' | '3' ,
  number   = digit+,
  addExpr  = addExpr '+' mulExpr
           | addExpr '-' mulExpr
           | mulExpr,
  mulExpr  = mulExpr '*' primExpr
           | mulExpr '/' primExpr
           | primExpr,
  primExpr = '(' expr ')'
           | number,
  expr     = addExpr
}
G.matchAll( '3*(1-2)', 'addExpr' )
alert(G.matchAll( '3*(1-2)', 'addExpr' ))






// Parser and simple interpreter via Semantic Actions
ometa CalcParser 
{
  digit    = ^digit:d                 -> d.digitValue(),
  number   = number:n digit:d         -> (n * 10 + d)
           | digit,
  addExpr  = addExpr:x '+' mulExpr:y  -> ['add', x, y]
           | addExpr:x '-' mulExpr:y  -> ['sub', x, y]
           | mulExpr,
  mulExpr  = mulExpr:x '*' primExpr:y -> ['mul', x, y]
           | mulExpr:x '/' primExpr:y -> ['div', x, y]
           | primExpr,
  primExpr = '(' expr:x ')'           -> x
           | number:n                 -> ['num', n],
  expr     = addExpr
}

str = "6*(4+3)";
parseTree = CalcParser.matchAll(str, 'expr') 
alert(parseTree);