python - Remove items from a list while iterating -

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i'm iterating on list of tuples in python, , attempting remove them if meet criteria. 

for tup in somelist:     if determine(tup):          code_to_remove_tup

what should use in place of code_to_remove_tup? can't figure out how remove item in fashion.

you can use list comprehension create new list containing elements don't want remove:

somelist = [x x in somelist if not determine(x)]

or, assigning slice somelist[:], can mutate existing list contain items want:

somelist[:] = [x x in somelist if not determine(x)]

this approach useful if there other references somelist need reflect changes.

instead of comprehension, use itertools. in python 2:

from itertools import ifilterfalse somelist[:] = ifilterfalse(determine, somelist)

or in python 3:

from itertools import filterfalse somelist[:] = filterfalse(determine, somelist)

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