Conditional operator in Python?

[Michael Hudson]

qrczak at knm.org.pl (Marcin 'Qrczak' Kowalczyk) writes:

> Sat, 31 Mar 2001 21:22:54 -0800, Erik Max Francis <max at alcyone.com> pisze:
> 
> > The Python FAQ, for instance, suggests x ? a : b can be reliably
> > substituted with
> > 
> >     (x and [a] or [b])[0]
> 
> It computes both a and b.

No it doesn't:

/>> def f():
|..  print 1
|..  return 1
\__ 
/>> def g():
|..  print 2
|..  return 2
\__ 
->> (0 and [f()] or [g()])[0]
2
2
->> (1 and [f()] or [g()])[0]
1
1

> A correct solution is
>     (0 and (lambda: a) or (lambda: b))()

This also works.

> Yes, it is ugly.

This is also true.

Cheers,
M.

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