Which of the following if statements is more Pythonic?
if not a and not b:
OR
if not (a or b):
It's not predicate logic so I should use the Python key words because it's more readable right?
Is the later solution more optimal than the other? (I don't believe so.)
Is there any PEP-8 guides on this?
Byte code of the two approaches (if it matters):
def func1():
if not a and not b:
return
def func2():
if not (a or b):
return
In [49]: dis.dis(func1)
2 0 LOAD_GLOBAL 0 (a)
3 UNARY_NOT
4 JUMP_IF_FALSE 13 (to 20)
7 POP_TOP
8 LOAD_GLOBAL 1 (b)
11 UNARY_NOT
12 JUMP_IF_FALSE 5 (to 20)
15 POP_TOP
3 16 LOAD_CONST 0 (None)
19 RETURN_VALUE
>> 20 POP_TOP
21 LOAD_CONST 0 (None)
24 RETURN_VALUE
In [50]: dis.dis(func2)
2 0 LOAD_GLOBAL 0 (a)
3 JUMP_IF_TRUE 4 (to 10)
6 POP_TOP
7 LOAD_GLOBAL 1 (b)
>> 10 JUMP_IF_TRUE 5 (to 18)
13 POP_TOP
3 14 LOAD_CONST 0 (None)
17 RETURN_VALUE
>> 18 POP_TOP
19 LOAD_CONST 0 (None)
22 RETURN_VALUE
I'd say whichever is easier for you to read, depending on what a and b are.