[ZPT] tal:repeat over the sorted keys of a dictionary

[Shane Hathaway]

Jean Jordaan wrote:
>>        <ul tal:repeat="key licenses/keys/format:sort">
>>            <li tal:content="licenses/key" />
>>        </ul>
> 
> 
> OK, then 'format' is a script that takes the output of 'keys', passes it 
> to 'sort', and returns the result? If it's ubiquitous, fine .. 
> otherwise, I like the 'dummy' route sans helper scripts more.

No.  "format:" is a namespace qualifier that tells ZPT to call a script 
in the standard formats module rather than look for an attribute or 
item.  Not all namespaces imply a module import, though.  Each namespace 
has a different meaning.  This mechanism is intended to be ubiquitous.

> Is '<li tal:content="licenses/key" />' a feature deriving from the 
> proposed changes? As is, it raises a KeyError on 'key'.

Oops, silly me.  Let me fix the bugs I introduced. :-)

   <ul tal:repeat="key licenses/call:keys/format:sorted">
    <li tal:content="licenses/key:?key" />
   </ul>

Yikes, that second expression is looking ugly.  Therefore, I would 
revert it to a Python expression:

   <ul tal:repeat="key licenses/call:keys/format:sorted">
    <li tal:content="python: licenses[key]" />
   </ul>

This is OK, but here's an alternative that would work if we added one 
more function to the standard formats module:

   <ul tal:repeat="item licenses/format:sorted_dict_items">
    <li tal:content="item/value" />
   </ul>

Shane