Re^2: in search of a more elegant if then else

It gets unreadable for all but the most trivial of expressions, but it's perfect for assigning one of two values to a variable. Also useful in that area are

                             # Use default when val is
my $var = $val || $default;  # ... false (= stringifies to '' or '0').
my $var = $val // $default;  # ... undefined. (Requires Perl 5.10.)
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Re^3: in search of a more elegant if then else by fullermd (Vicar) on Feb 19, 2010 at 06:34 UTC
It gets unreadable for all but the most trivial of expressions Right. It's possible to back yourself (or front yourself, if you're twisted :) into monstrosities with it. The classic C 12 Days of Christmas puts it to good (?) use, among its other distortions. Like a lot of things in perl (or any language, really), you just have to keep an eye on yourself to be sure you stay inside the lines. My two rules of thumb are length and nestedness: If I start nesting, that's a sign I should write it out in more explicit form If it starts getting much longer than 1 line, or there're more than maybe one or two logical ops (`&&`, `\|\|`, etc) in the condition, I should probably switch to if/else (None hard rules of course, but signs that I'm wandering off the beam and should take a step back to reevaluate)	[reply] [d/l] [select]

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Re^3: in search of a more elegant if then else
by fullermd (Vicar) on Feb 19, 2010 at 06:34 UTC

It gets unreadable for all but the most trivial of expressions

Right. It's possible to back yourself (or front yourself, if you're twisted :) into monstrosities with it. The classic C 12 Days of Christmas puts it to good (?) use, among its other distortions.

Like a lot of things in perl (or any language, really), you just have to keep an eye on yourself to be sure you stay inside the lines. My two rules of thumb are length and nestedness:

If I start nesting, that's a sign I should write it out in more explicit form
If it starts getting much longer than 1 line, or there're more than maybe one or two logical ops (&&, ||, etc) in the condition, I should probably switch to if/else

(None hard rules of course, but signs that I'm wandering off the beam and should take a step back to reevaluate)

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