Paul McGuire wrote:
> While sifting through some code looking for old "x and y or z" code
> that might better be coded using "y if x else z", I came across this
> puzzler:
>
> x = <boolean expression> and True or False
>
> What is "and True or False" adding to this picture? The boolean
> expression part is already evaluating to a boolean, so I don't
> understand why a code author would feel compelled to beat this one
> over the head with the additional "and True or False".
>
> I did a little code Googling and found a few other Python instances of
> this, but also many Lua instances. I'm not that familiar with Lua, is
> this a practice that one who uses Lua frequently might carry over to
> Python, not realizing that the added "and True or False" is redundant?
>
> Other theories?
If it were e. g.
def f():
big_beast = list(range(10**100))
return big_beast and True or False
x = f()
it would prevent that a big_beast reference becomes visible outside the
function and allow for immediate release of its memory.
Peter
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