Open file and with statement in Python -


i have function like:

def func(filename):     open(filename) f:         return [line.split('\t')[0] line in f]

is "with" statement closing file when there 'sudden' function return? can ignore "with" statement? i.e. safe , equivalent (from memory leak perspective) do,

def func(filename):     return [line.split('\t')[0] line in open(filename)]

?

it's safe. context manager's __exit__ called if return while inside of context, file handle closed.

here's simple test:

class contexttest(object):     def __enter__(self):         print('enter')      def __exit__(self, type, value, traceback):         print('exit')  def test():     contexttest() foo:         print('inside')         return

when call test(), get:

enter inside exit

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