It _is_ getting called. For some reason, your Debug.write is failing to send any output:

lzx> Debug.trace(canvas, 'laszloMethod')
lzx> [1,2,3].sort(canvas.laszloMethod)
TRACE: [394491.00] laszloMethod.apply(«undefined», [1, 2])
laszloMethod( 1 , 2 )
TRACE: [394501.00] laszloMethod -> 0
TRACE: [394505.00] laszloMethod.apply(«undefined», [1, 3])
laszloMethod( 1 , 3 )
TRACE: [394512.00] laszloMethod -> 0
TRACE: [394516.00] laszloMethod.apply(«undefined», [1, 2])
laszloMethod( 1 , 2 )
TRACE: [394523.00] laszloMethod -> 0
TRACE: [394527.00] laszloMethod.apply(«undefined», [2, 3])
laszloMethod( 2 , 3 )
TRACE: [394536.00] laszloMethod -> 0
«Array(3)#15| [1, 2, 3]»
lzx>

Oh, hah-hah. I see why. Because laslzoMethod is a method, it expects a 'this' argument, and our compiler inserts an implicit `with (this)` around your method body, but you are calling it as a function, and `this` is undefined in that case (see the trace output above). So your code is turning into `with (undefined)` and I bet that causes the global reference to Debug to fail. Amusingly, tracing the method makes the debug output work. I can't really explain that.

If you were to make a closure to call your method, it should work:

lzx> Debug.untrace(canvas, 'laszloMethod')
lzx> [1,2,3].sort(function (a, b) { return canvas.laszloMethod(a, b) })
laszloMethod( 1 , 2 )
laszloMethod( 1 , 3 )
laszloMethod( 1 , 2 )
laszloMethod( 2 , 3 )
«Array(3)#57| [1, 2, 3]»
lzx>

On 2008-01-09, at 14:28 EST, Pablo Kang wrote:

Btw, I know that I can call a laszloMethod from a Javascript function like:

 <method name="javascriptFunction" args="n1,n2">
     return canvas.laszloMethod(n1,n2);
 </method>

What I want to know is why it is I can't pass in the the laszloMethod directly.

Thanks,
pablo

On Wed, 9 Jan 2008, Pablo Kang wrote:

Anyone know why passing in a function defined with an LZX method tag into Array.sort doesn't work? Here's a test case:

<canvas debug="true">

  <method name="laszloMethod" args="n1,n2">
      Debug.write('laszloMethod(', n1, ',', n2, ')');
      return 0;
  </method>

  <script>
      function javascriptFunction(n1,n2) {
          Debug.write('javascriptFunction(', n1, ',', n2 ,')');
          return 0;
      }
  </script>

  <handler name="oninit">
      var arr = [ 1,2,3 ];

      Debug.write('-- Javascript Function --');
      arr.sort( javascriptFunction );

      Debug.write('-- Laszlo Method --------');
      arr.sort( canvas.laszloMethod );
  </handler>

</canvas>

pablo





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