UserLinux chooses Python as "interpretive language" of choice

[Paul Moore]

Oren Tirosh <oren-py-l at hishome.net> writes:

> I've always considered the visitor pattern as a rather poor substitute 
> for generators, not as a something worth having for its own sake. Using 
> generators instead of visitors+anonymous functions obviously reduces the 
> need for anonymous functions (not that it's any excuse for not having 
> something better than Python's lambdas!).  

This is a bit out of context, as I've not read the full thread here,
but while I can see that the visitor pattern doesn't offer anything
much over generators for a *single* visitor function, I'm not sure how
that generalises to visitors with multiple "visit" methods.

Consider a file-tree walker, which takes a visitor. On each directory
seen, the visit_directory() method is called, on each file seen, the
visit_file() method is called, and on each symlink seen, the
visit_symlink() method is called.

Replacing that with generators seems like it may be clumsy. Or have I
missed a simple transformation?

Paul.
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