[Python-ideas] Reference variable in assignment: x = foo(?)

[David Mertz]

On Thu, Jul 11, 2013 at 4:57 PM, Joao S. O. Bueno <jsbueno at python.org.br>wrote:

> I don't know if what I miss most is the samething the OP is asking for -
> but the idea of re-using a value retrieved in an expression in the
> same expression - without the need
> to assign to a temporary variable.
>
> Like in:
>   value = expensive_function(b)  if expensive_function(b) else
> default_value
>
> (of course this is a trivial example - but nonetheless it would require an
> extra "if" statement to avoid the double call)
>

How about:

  value = expensive_function(b) or default_value

One call, exact same behavior as you request.  Available since Python 1.0.


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