dict.get(key, default) evaluates default even if key exists
Mark Polesky
markpolesky at yahoo.com
Tue Dec 15 12:07:16 EST 2020
Hi.
# Running this script....
D = {'a':1}
def get_default():
print('Nobody expects this')
return 0
print(D.get('a', get_default()))
# ...generates this output:
Nobody expects this
1
###
Since I'm brand new to this community, I thought I'd ask here first... Is this worthy of a bug report? This behavior is definitely unexpected to me, and I accidentally coded an endless loop in a mutual recursion situation because of it. Calling dict.get.__doc__ only gives this short sentence: Return the value for key if key is in the dictionary, else default. Nothing in that docstring suggests that the default value is evaluated even if the key exists, and I can't think of any good reason to do so.
Am I missing something?
Thanks,
Mark
More information about the Python-list
mailing list