[Zope3-dev] zope.i18n.translate ignores keyword arguments: desired/expected?

[Gary Poster]

Hi all.  in zope/i18n/__init__.py, the _translate method used by  
translate, if the msgid is a MessageID or a Message then the domain,  
default, and mapping are all used in preference to keyword arguments,  
even if, for instance, the keyword is non-None and the attribute is  
None.

Because of the immutability of Message, it would be nice if,  
minimally, the mapping keyword were honored.

My strawman is that all non-None `translate` keyword arguments should  
win over msgid values.

A valid counter-argument for domain, at least, is that this is really  
an attribute of the msgid, and overriding it effectively changes the  
msgid into an entirely different token.  But I'm tempted to go with  
simple logic and just say 'keywords override msgids'.

This seems to be in direct opposition with the current code, so I'm  
guessing someone put some thought behind the current behavior.  Would  
anyone care to champion it?

Gary