Page Templates define
I define a variable in a tag, and try and use it in a contained tag, and get a NameError on that variable. Can anyone help me understand why? The snippet of code is below: <html metal:use-macro="here/GetTemplate" tal:define="objs here/regionObjects; num_objs python:objs[0] "> <div metal:fill-slot="body"> <table border="0" width="100%" tal:condition="python:num_objs > 11"
... Error Type: NameError Error Value: global name 'num_objs' is not defined
This is the answer from Tres when I had the same problem: """ AFAIK, global names are defined in the scope of the template which includes the macro; the "source" template for the macro is not itself "evaluated" before inclusion (METAL processing is done *before* TAL processing). """ --On Sonntag, 27. Oktober 2002 13:23 -0700 Mark Gibson <mark@dimensional.com> wrote:
I define a variable in a tag, and try and use it in a contained tag, and get a NameError on that variable. Can anyone help me understand why? The snippet of code is below:
<html metal:use-macro="here/GetTemplate" tal:define="objs here/regionObjects; num_objs python:objs[0] ">
<div metal:fill-slot="body"> <table border="0" width="100%" tal:condition="python:num_objs > 11"
...
Error Type: NameError Error Value: global name 'num_objs' is not defined
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--------------------------------------------------------------------- - Andreas Jung http://www.andreas-jung.com - - EMail: andreas at andreas-jung.com - - "Life is too short to (re)write parsers" - ---------------------------------------------------------------------
Ahh, Ok. It all makes sense now. So to make something *truly* global to a template, and all processing done within that template, I define variables before an processing is done. So, my example below turns into this: <span tal:omit-tag="" tal:define="objs here/regionObjects; num_objs python:objs[0];"> <html metal:use-macro="here/GetTemplate"> ... </html> </span> This seems a little sloppy. Is there a better way to do it? This also leads me to believe that there's no way to define site-wide globals available in every Page Template that's generated. What if I wanted a module available in every page without having to define it in every page? e.g: tal:define="global pps modules/Products/PythonScripts/standard" I can't really get this to work, can I? Mark
This is the answer from Tres when I had the same problem:
""" AFAIK, global names are defined in the scope of the template which includes the macro; the "source" template for the macro is not itself "evaluated" before inclusion (METAL processing is done *before* TAL processing). """
--On Sonntag, 27. Oktober 2002 13:23 -0700 Mark Gibson <mark@dimensional.com> wrote:
I define a variable in a tag, and try and use it in a contained tag, and get a NameError on that variable. Can anyone help me understand why? The snippet of code is below:
<html metal:use-macro="here/GetTemplate" tal:define="objs here/regionObjects; num_objs python:objs[0] ">
<div metal:fill-slot="body"> <table border="0" width="100%" tal:condition="python:num_objs > 11"
...
Error Type: NameError Error Value: global name 'num_objs' is not defined
_______________________________________________ Zope maillist - Zope@zope.org http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
--------------------------------------------------------------------- - Andreas Jung http://www.andreas-jung.com - - EMail: andreas at andreas-jung.com - - "Life is too short to (re)write parsers" - ---------------------------------------------------------------------
Hi Mark, you should avoid heavy calculations in a page template. Better use a python script, which can be aquired, and call it in the template whereever you need it. To avoid long running calculations every time if you call the script multiple times in a template, you can use the following construct: if request.has_key('_yourspecialkey'): return request['_yourspecialkey') value=your routine request.set('_yourspecialkey',value) return value Remember, you can construct and return a fairly complex object Structure, like a list or dictionary or list of dictionaries (preferred) where you can use simple path expressions in your template. HTH Tino
Ahh, Ok. It all makes sense now.
So to make something *truly* global to a template, and all processing done within that template, I define variables before an processing is done.
So, my example below turns into this:
<span tal:omit-tag="" tal:define="objs here/regionObjects; num_objs python:objs[0];">
<html metal:use-macro="here/GetTemplate">
...
</html> </span>
This seems a little sloppy. Is there a better way to do it?
This also leads me to believe that there's no way to define site-wide globals available in every Page Template that's generated. What if I wanted a module available in every page without having to define it in every page? e.g:
tal:define="global pps modules/Products/PythonScripts/standard"
I can't really get this to work, can I?
Mark
This is the answer from Tres when I had the same problem:
""" AFAIK, global names are defined in the scope of the template which includes the macro; the "source" template for the macro is not itself "evaluated" before inclusion (METAL processing is done *before* TAL processing). """
--On Sonntag, 27. Oktober 2002 13:23 -0700 Mark Gibson <mark@dimensional.com> wrote:
I define a variable in a tag, and try and use it in a contained tag, and get a NameError on that variable. Can anyone help me understand why? The snippet of code is below:
<html metal:use-macro="here/GetTemplate" tal:define="objs here/regionObjects; num_objs python:objs[0] ">
<div metal:fill-slot="body"> <table border="0" width="100%" tal:condition="python:num_objs > 11"
...
Error Type: NameError Error Value: global name 'num_objs' is not defined
_______________________________________________ Zope maillist - Zope@zope.org http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
--------------------------------------------------------------------- - Andreas Jung http://www.andreas-jung.com - - EMail: andreas at andreas-jung.com - - "Life is too short to (re)write parsers" - ---------------------------------------------------------------------
_______________________________________________ Zope maillist - Zope@zope.org http://lists.zope.org/mailman/listinfo/zope ** No cross posts or HTML encoding! ** (Related lists - http://lists.zope.org/mailman/listinfo/zope-announce http://lists.zope.org/mailman/listinfo/zope-dev )
Mark Gibson writes:
I define a variable in a tag, and try and use it in a contained tag, and get a NameError on that variable. Can anyone help me understand why? The snippet of code is below:
<html metal:use-macro="here/GetTemplate" tal:define="objs here/regionObjects; num_objs python:objs[0] "> TAL attributes on a metal "use-macro" tag are ineffective (as the complete tag is replaced by the macro, including the TAL attributes.
Dieter
participants (5)
-
Andreas Jung -
Dieter Maurer -
Mark Gibson -
mark＠dimensional.com
-
Tino Wildenhain