a = b = 1 just syntactic sugar?
staschuk at telusplanet.net
Sun Jun 8 17:48:21 CEST 2003
Quoth Ed Avis:
> Oh. I thought someone said on this newsgroup only a few days ago that
> they did not, when I mentioned that
> cond and x or y
> is a well-known substitute for a conditional operator like C's
> (cond ? x : y) or Haskell's (if cond then x else y). Someone said
> that it wouldn't work, because x and y would be evaluated in either
No. Here's what Terry said:
"This conditional selection expression (which I have used) works as a
substitute for part of certain if-else statements if and only if
bool(if_expression) == True [...]"
By "if_expression" here he means what you call "x" above. Note
what happens if x is false:
>>> cond = True
>>> cond and 0 or 1
This form works only for true x. There's another form, as Terry
discovered back in February, which works for false x (and only for
false x). But obviously one would prefer an expression which has
the desired behaviour no matter what x is.
Steven Taschuk staschuk at telusplanet.net
"What I find most baffling about that song is that it was not a hit."
-- Tony Dylan Davis (CKUA)
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