Re^2: Useless unless

/me waits for tye to rebut this ;-)

Anyway, I agree on both the spanning statements and the usability of unless. To me, unless is way better than "if not $foo". However, anything more complex is often easier to write and read as an if:

  ... unless $foo and not $bar->baz()
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Switch that around to if, and it's easier to parse, I think.

  ... if not $foo or $bar->baz()
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Still not easy, but I think that's an improvement of at least half a step.

Back to the otherwise statement. Here's just something to throw out there, more to provoke thought than as a serious suggestion. Rather than separating two statements, what would you think of:

  $a if $b, otherwise $c;
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Arguably, it's a single statement still. I think I still prefer the full if ($b) { $a } else { $c } version. But at least it deals with the "span statements" issue. Somewhat.

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Re^3: Useless unless by chromatic (Archbishop) on Aug 06, 2005 at 05:22 UTC
The problem with `not` and `unless` is double-negation, which is complex. I only use `unless` in postfix statement form, and I never use it if there's a `not`. The problem with a negation and multiple conditionals is the same as in English -- ambiguity of the distributiveness of the negation. That's a case where parenthesizing helps.	[reply] [d/l] [select]
Re^3: Useless unless by friedo (Prior) on Aug 06, 2005 at 04:10 UTC
I still don't think I quite get this `otherwise` groove. Would `$a if $b, otherwise $c;` [download] Be equivalent to `$b ? $a : $c;` [download] ? If so, I guess that's kinda cool, if a little confusing. We already have differently-binding text equivalents for the usual symbolic logical operators, why not the good ol' ternary conditional? FWIW, I use `unless` instead of `if !` all the time. In fact, I am routinely dissapointed by the fact that we don't have a built-in `elsunless`. :)	[reply] [d/l] [select]