[Ben Ocean]

At 06:43 PM 10/23/01 +0400, you wrote:

...

On Tue, Oct 23, 2001 at 07:31:21AM -0700, Ben Ocean wrote:

...

...

Do not use DTML inside DTML. <img src="images/top" width=<dtml-var sizeCalc(1008,size)>...

You should call it like this: <dtml-var "sizeCalc(1008, size)">. And if you receive an error about "size" - there is a problem with that size, and you should fix the problem with the size, not with the External Method.

I'm confused. If I plug <dtml-var size> anywhere else in the above script it prints *1*. In other words, I have a dtml method called *size* and the only thing in it is the number 1. If I replace *size* with the number 1 in the above <img> tag, width yields 1008 as it should (1008*1). So I don't understand why the <dtml-var size> doesn't work when called as *size* in the External Method. What am I missing?

When you say <dtml-var size>, Zope discovers that "size" is an external Python function and makes a Python call size() (simplified but close enough). When you say <dtml-var function_call(parm1,parm2)>, you get an error because DTML does not understand the syntax, Instead, you must write <dtml-var "function_call(parm1,parm2)">. When it sees the quotation marks, Zope sends the quoted string to Python to be evaluated, with some context information so Python can find the values of Zope properties and variables. But Python isn't going to know to call a Zope function to evaluate an External Method. If Python can't evaluate one of the parameters because it is a DTML thing, you can just evaluate it before calling the External Method, like this: <dtml-let Size=size> <dtml-var "sizeCalc(1008,Size)"> </dtml-let> This way, Python has an ordinary Zope variable to find, which it can get from the environment it receives. Cheers, Tom P