[Python-ideas] Leave off "else" in ternary expression

[David Mertz]

This seems pretty nonsensical to me. Ternaries are not only used in simple
assignments.

E.g. 'myfunc(a, b if pred else c, d)' is common and obvious.

'myfunc(a, b if pred, d)' is strange with no obvious semantics.

On Oct 28, 2016 11:29 AM, "Todd" <toddrjen at gmail.com> wrote:

> The null-coalescing discussion made me think about the current ternary "x
> = a if b else c" expression.  In normal "if / else" clauses, the "else" is
> optional.  I propose doing the same thing with ternary expressions
> (although I don't know what the result would be called, a "binary
> expression"?)
>
> The idea would be to allow this syntax:
>
> x = a if b
>
> Which would be equivalent to:
>
> x = a if b else x
>
> I think this would be useful syntax.  In particular, I see it being useful
> for default value checking, but can also be used to override the result of
> particular corner cases from functions or methods..
>
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