Re: Way for see if dict has a key

Fredrik Lundh wrote:
"André" wrote:


Perhaps Bruno meant this:

try:
... my_dict[key] ...
except:
...

when we expect that the key will most often be in my_dict so that
exception will be raised rarely, otherwise use


on my machine, "key in dict" is about twice as fast as the full try/getitem con-
struct when the key is present in the dict,

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

so that's not a very good optimization.

FWIW, I personaly didn't meant to present it as an optimisation - just
as one more possible way to test the existence of a given key...

now, if the OP had been interested in the associated value, things might have
been a bit different.

</F>





--
bruno desthuilliers
python -c "print '@'.join(['.'.join([w[::-1] for w in p.split('.')]) for
p in 'onurb@xxxxxxxxxxx'.split('@')])"
.

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