[Zope3-Users] emacs with metal and tal namespaces

[Perry Smith]

On Oct 29, 2006, at 10:43 AM, Fred Drake wrote:

> On 10/29/06, Perry Smith <pedz at easesoftware.com> wrote:
>> I bumped into two problems that stumped me.  First, it is general  
>> practice
>> to do:
>>
>> <metal:arbitrary_tag define-macro="page">
>
> Constructs for this can be written in RELAX NG, but I've not tried
> doing that myself though.  The Atom specification includes an example
> for elements in the XHTML namespace.

It is simple to have specify a tag like metal:* where anything can  
follow.  But I did not see the benefit to that.

>
>> Second, metal and tal constructs are attributes that are placed  
>> inside any
>> tag.
> ...
>> So, to really do this properly, each schema that the tal or metal  
>> are going
>> to be used in would need to be modified to allow the tal and metal
>> attributes.  The RNC syntax does have a funny include construct  
>> that allows
>> overriding constructs that are defined in the included file.  But,  
>> that only
>> means that it would be possible to create a maintenance nightmare  
>> if someone
>> wanted to do that.
>
> Almost; it really depends on the how the base schemas are written.
> They can be written to cooperate with extending or specializing
> schemas.  There are examples in the RELAX NG tutorials.  It does
> require that the base schemas be written with that expectation, just
> like classes need to be written to expect subclassing.

Yes.  thats true.  The samples I have for xhtml did not seem to have  
that.  For example, in my xhtml, the title element allowed the  
xml:lang attribute and nothing else.  I got my samples from the nxml  
emacs package.

But, I think I can still do some useful work here.

I can create a rnc for metal and tal.  It can have hooks to let  
people add to the list of tags (which solves the first problem) and  
it could create a list (or two lists) of attributes that future  
schema writers could add into their schema.

Aside from xhtml and zcml, (for 99% of the usage), what is the list  
of base schemas people are going to add metal and tal attributes to?

It also sounds like I need to look at the tutorials.  I was just look  
at the spec.  Maybe there are conventions that I missed.