5.10: “Equal To One Of” Trick with the in Operator
- Page ID
- 14501
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The expression event.key in (K_LEFT, K_a)
is just a Python trick to make the code simpler. It is a way of saying "evaluate to True
if event.key
is equal to one of K_LEFT
or K_a
". The following two expressions will evaluate the exact same way:
event.key in (K_LEFT, K_a) event.key == K_LEFT or event.key == K_a
You can really save on some space by using this trick when you have to check if a value is equal to one of multiple values. The following two expressions will evaluate the exact same way:
spam == 'dog' or spam == 'cat' or spam == 'mouse' or spam == 'horse' or spam == 42 or spam == 'dingo' spam in ('dog', 'cat', 'mouse', 'horse', 42, 'dingo')