Antoon Pardon wrote:
> Op 2005-06-29, Scott David Daniels schreef <[EMAIL PROTECTED]>:
>
>>Roy Smith wrote:
>>
>>>Andrew Durdin <[EMAIL PROTECTED]> wrote:
>>>
>>>>Corrected version:
>>>> result = [(lambda: expr0), lambda: expr1][bool(cond)]()
>>
>>Sorry, I thought cond was a standard boolean.
>>Better is:
>> result = [(lambda: true_expr), lambda: false_expr][not cond]()
>
>
> How about the following:
>
> result = (cond and (lambda: true_expr) or (lambda: false_expr))()
>
That works as long as long as they are expressions, but the ? format
does seem to be more concise I admit.
To use *any* expressions in a similar way we need to use eval which is a
lot slower unfortunately.
result = eval(['expr0','expr1'][cond])
A thought occurs to me that putting index's before the list might be an
interesting option for expressions.
result = expr[expr0,expr1]
This would probably conflict with way too many other things though.
Maybe this would be better?
result = index from [expr0,expr1]
Where index can be an expression. That is sort of an inline case
statement. Using a dictionary it could be:
result = condition from {True:expr1, False:expr0}
As a case using values as an index:
case expr from [
expr0,
expr2,
expr3 ]
Or using strings with a dictionary...
case expr from {
'a':expr0,
'b':expr1,
'c':expr3 }
else:
expr4
Reads nice, but can't put expressions in a dictionary or list without
them being evaluated first, and the [] and {} look like block brackets
which might raise a few complaints.
Can't help thinking of what if's. ;-)
Cheer's
Ron
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