[Zope] Using fmt= with External Method

[Alexander Staubo]

I have not seen any documentation on this, so I'm definitely fumbling in
the dark here. Please bear with me.

I'm curious if it's possible to use the fmt= syntax with external
methods. Basically, let's assume I have this piece of DTML:

  <!--#var Heading fmt=HeadingFormat-->

If I add an External Method called HeadingFormat, that method should be
called to format Heading, right?

Well, this works partially, except that HeadingFormat() cannot take any
parameters. Any reason for this? How, then, can I access the data to
format?

Looking at the code in DT_Var.py:

                if hasattr(val, fmt):
                    print "calling %s" % fmt #!!
                    val = getattr(val,fmt)()
                elif special_formats.has_key(fmt):
                    val = special_formats[fmt](val, name, md)
                elif fmt=='': val=''
                else: val = fmt % val

Shouldn't the line

                    val = getattr(val,fmt)()

say something like

                    val = getattr(val,fmt)(val)

instead? (Implementing the above patch seems to work, but is likely to
break lots of things?)

Did I miss something? Since chances are this is the case :-), how then
do I implement a method to format arbitrary objects without actually
modifying the Zope sources?

--
Alexander Staubo             http://www.mop.no/~alex/
"`This must be Thursday,' said Arthur to himself, sinking low over
his beer, `I never could get the hang of Thursdays.'"
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