[Python-Dev] iterator API in Py3.0 (original) (raw)

Jeremy Hylton jeremy at alum.mit.edu
Fri Mar 3 22:09:34 CET 2006

On 3/3/06, Raymond Hettinger <raymond.hettinger at verizon.net> wrote:

The double underscore convention is appropriate where the method is always invoked magically in normal code and not called directly. The next() method is differenct because it is a mixed case, sometimes called magically and sometimes called directly. In the latter case, the name is highly visible and therefore should not have double underscores.

I suspect that those who feel differently are ones who usually avoid calling next() directly. That's okay, but we shouldn't muck-up the naming for the rest of us who often do have a need to use next(). This is doubly important because we're now expanding the protocol to include send() and throw(). Adding underscores around them too will only make those methods look harder to use than they actually are. Don't underestimate the psychological revulsion to calling code filled with piles of double underscores.

I think it is a little odd that next is not spelled next, but I appreciate the reasons given here in particular. Every time I right .next(), I'm happy that it doesn't have underscores.

Jeremy

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