For review: PEP 308 - If-then-else expression

Paul Moore gustav at morpheus.demon.co.uk
Sat Feb 8 17:28:08 EST 2003


"Andrew Dalke" <adalke at mindspring.com> writes:

> As I mentioned elsewhere, I've scanned the Linux kernel for use
> of the ?: operator.  It isn't used all that often, and most cases can
> be implemented in Python with the
>    [false, true][expr comparison value]
> construct or with the
>   x = y or default_value
> construct.

Actually, in C, I often find that I *can't* use the ternary operator,
because what I want is a default. So

    x = y or default

is more useful to me. (But Python already has that).

> I would rather see some better examples of when people would like to
> use the if/else expression.  People have pointed out that it can do
> short circuiting, but in the real-life uses I saw in the kernel it
> didn't make a different if there was short circuiting or not.

Yes, I thing the short-circuit argument is spurious. No-one has given
a telling example which needs it.

Paul.
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