>> if False:
>>
>> (indented) block of code here is commented out
>> I've no idea how efficient it is compared to triple-quoted strings or
>> line by line comments.
Gustavo> Actually, it's infinitly [sp?] more defficient (contrary of
Gustavo> efficient?) than triple-quoted strings or line-by-line
Gustavo> comments, because those two never make it to execution stage,
Gustavo> because they're dropped by the compiler. :-)
If you use 'if 0:' the 2.4 byte code compiler also deletes it:
>>> import dis
>>> def f(a):
... if False:
... return a
... return a+1
...
>>> dis.dis(f)
2 0 LOAD_GLOBAL 0 (False)
3 JUMP_IF_FALSE 8 (to 14)
6 POP_TOP
3 7 LOAD_FAST 0 (a)
10 RETURN_VALUE
11 JUMP_FORWARD 1 (to 15)
>> 14 POP_TOP
4 >> 15 LOAD_FAST 0 (a)
18 LOAD_CONST 1 (1)
21 BINARY_ADD
22 RETURN_VALUE
>>> def g(a):
... if 0:
... return a
... return a+1
...
>>> dis.dis(g)
4 0 LOAD_FAST 0 (a)
3 LOAD_CONST 1 (1)
6 BINARY_ADD
7 RETURN_VALUE
The 'if False:' case isn't optimized because you can (today, anyway)
redefine or override False.
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