[Tutor] hash

[Andreas Kostyrka]

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Simple, defining __hash__ on a class allows you to supply a hash value
for instances of your class.

andreas at andi-lap:~> cat /tmp/hash.py
class X:
    def __hash__(self):
        print "HASH CALLED"
	return 123

print hash(X())
andreas at andi-lap:~> python /tmp/hash.py
HASH CALLED
123

Andreas

linda.s wrote:
> what is the use of def __hash__(self)?
> I can not understand the document.
> any example? thanks,
> Linda
> _______________________________________________
> Tutor maillist  -  Tutor at python.org
> http://mail.python.org/mailman/listinfo/tutor
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