Possible eval/templet bug

"Marc Palmer" <[email protected]> Fri, 05 Aug 2005 11:46:41 +0100
Newsgroups gmane.comp.java.webmacro.user
Message-ID <[email protected]> 
Hi,

I've hit upon what I believe is an obscure bug in #eval/#templet in 2.0 RC1.

I'm finding it with my JSP taglib but I don't believe it is specific to
the taglib, it smells more like a problem with #templet/eval. Of course a
unit test will prove this so that will naturally be my next course of
action. However I can't commit to WM from my workplace.

...evaluating this template:

<html>
<body>

#templet $render

Value is: $value

#end

#templet $outerTemplet
   
  #set $value = "Hello!"
  #eval $rendertemplet using {
	"value" : $value
  }

#end

#eval $outerTemplet using {
    "rendertemplet" : $render
}

</body>
</html>


...the intention/expectation is that this will simply output:


<html>
<body>

Value is: Hello!

</body>
</html>


...but, rather weirdly, you get this:


<html>
<body>

Value is: <!-- Attempted to write an undefined variable: Hello! at
render:4.11 -->

</body>
</html>

Notice that it says undefined variable "Hello!" - but that is the value of
the variable! It's like it's trying to recursively evaluate it.

Keats - any thoughts?

I will try to dig into the source and write a unit test for this, but I
wanted to flag it in case I'm being stupid.

Also, there seems to be an error handling bug. If your innermost templet
references a non-existent variable, you get something like:

Value is: <!-- Attempted to write an undefined variable: <!-- Attempted to
write an undefined variable: $iknowthisdoesntexistvalue at unknown:2.58
--> at render:4.11 -->


...notice that this has two error messages and unbalanced "-->" so you get
some nasty output in the page and interestingly two sources - unknown and
render. Also note that it gets the error variable name right in this case,
but in the first problem I talked about it uses the -value- of the
variable as the "unknown" variable name.

Very confusing!

Cheers



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