[Python-Dev] __contains__ hook

[Moshe Zadka]

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Here's a very preliminary, very hackish version of a hook for the "in"
operator. 

Basically, use like:

class spam:
	def __contains__(self, o):
		return 1
6 in spam() (answers 1)

I must say I was horrified by the current way the operator was handled:
very non-OO-ish. I'd much rather there'd be a slot in the sequence
interface for this method. This is why there's still no way to use the
hook with regular C extension types.

Have fun!

(BTW: I've tested it only minimally, so it might break your Python. Use
with caution).

PS.
Eric, you can implement sets the *right* way this time.

--
Moshe Zadka <mzadka@geocities.com>. 
INTERNET: Learn what you know.
Share what you don't.

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