Re: Way for see if dict has a key

Bruno Desthuilliers wrote:
Fredrik Lundh wrote:
Bruno Desthuilliers wrote:

on my machine, "key in dict" is about twice as fast as the full

try/getitem construct when the key is present in the dict,


Doesn't it depends on the number of keys in the dict ?


why would it depend on the number of keys in the dict ?

</F>

Seems that if "key in dict" do a simple linear search, it depends on the
number of keys in dict (and the position of the searched key etc...).

And if I'm missing the point and you it and you know why, it would be
simple to explain than to answer my question with another question.


maybee we can imagine that key in dict
just perform
try:
dict[key]
return True
except KeyError:
return False

If I understand correctly, it will be time constant no ??
just the needed time to compute the hash for the key

Eric

.

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