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[Python-Dev] replacing 'global'

Phillip J. Eby pje at telecommunity.com
Sun Oct 26 11:06:10 EST 2003 
At 04:54 PM 10/26/03 +0100, Just van Rossum wrote:
>My question above is misleading with respect to my personal feelings
>about the issue. It should have been:
>
>"""*If* we decide we need to be able to assign to names in outer scopes,
>would it be a good idea to add a rebinding operator?"""
>
>I actually don't care much whether the cability is added or not, but
>*if* we add it, I'd much rather see a rebinding operator than an
>extension to the global statement or a new declarative statement.

If we have a rebinding operator, I'd rather it be something considerably 
more visible than the presence or absence of a ':' on an assignment 
statement.  So far, all the examples have been downright scary in the 
invisibility of what's happening.  Mostly, I can imagine some poor sap 
trying to debug a program that uses := and is missing one somewhere or has 
one where it's not intended -- and hoping that poor sap won't be me.  :)

I've mostly stayed out of this discussion, but so far something like the 
scope(function).variable proposals, with perhaps a special case for 
scope(global) or scope(globals) seems to me like the way to go.  It seems 
very Pythonic, in that it is explicit and calls attention to the fact that 
something special is going on, in a way that ':=' does not.  And 'scope' 
can be looked up in a manual more easily than ':=' can.  Last, but not 
least, ':=' looks enough like normal assignment in other languages, that 
somebody just plain might not notice that they *need* to look it up.
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