Is it possible to use 'else' in a python list comprehension?
Here is the code I was trying to turn into a list comprehension:
table = ''
for index in xrange(256):
if index in ords_to_keep:
table += chr(index)
else:
table += replace_with
Is there a way to add the else statement to this comprehension?
table = ''.join(chr(index) for index in xrange(15) if index in ords_to_keep)
The syntax a if b else c is a ternary operator in Python that evaluates to a if the condition b is true - otherwise, it evaluates to c . It can be used in comprehension statements:
>>> [a if a else 2 for a in [0,1,0,3]]
[2, 1, 2, 3]
So for your example,
table = ''.join(chr(index) if index in ords_to_keep else replace_with
for index in xrange(15))
If you want an else you don't want to filter the list comprehension, you want it to iterate over every value. You can use true-value if cond else false-value as the statement instead, and remove the filter from the end:
table = ''.join(chr(index) if index in ords_to_keep else replace_with for index in xrange(15))
To use the else in list comprehensions in python programming you can try out the below snippet. This would resolve your problem, the snippet is tested on python 2.7 and python 3.5.
obj = ["Even" if i%2==0 else "Odd" for i in range(10)]