[Ometa] Translation problem in OMeta/JS (was: timeout problem)

[Rüdiger Plantiko]

Der OMeta friends,

I could bring the problem to the point (it has nothing to do with negation):

Go to the OMeta/JS workspace http://www.tinlizzie.org/ometa-js/.

Then define the following simple oMeta object:

ometa M {
  test   = 'x':x 'y':y -> x + y
}

Now try to match the string 'xy':

M.matchAll( 'xy', 'test' )

>>> You will get an endless loop !

The JS transcript shows that for some unknown reasons the "->" is
swallowed. The test rule is treated as if I had written

test = 'x':x 'y':y x+ y

Since the "rule" x always retrieves the character 'x', the expression x+
blows up the result array with 'x' characters and never takes an end.

Here is the generated transcript of the above rule:

"test":function(){
  var $elf=this,_fromIdx=this.input.idx,x,y;
  return
    (function(){
      x=this._applyWithArgs("exactly","x");
      y=this._applyWithArgs("exactly","y");
      this._many1((function(){return x}));
      return this._apply("y")
    }).call(this)}

The rule can easily be saved by enclosing the semantic action into braces
like so:

ometa M {
  test   = 'x':x 'y':y -> { x + y }
}

But I don't understand why the first way is not transcribed as I expected
(and probably all of you would expect).

Regards,
Rüdiger





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