In perl, it's counter-intuitive to say something like:

do_something() if(COND);
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Abigail

I didn't mean that "just in perl" it's counter-intuitive, I meant, the way perl forces you to do it is counter-intuitive. Of course what is intuitive differs depending on the person, I just find it much more natural to put the condition first. I would never say, "I use my umbrella if it rains." I would say, "If it rains, I'll use my umbrella." Of course as the reply stated below, I could wrap the whole thing in parens and use && but that (IMO of course) is still not as intuitive as saying if(COND) do_something(); I've been working with perl now for years and I still pause and scratch my head when I see that in code. I fear I'll never get used to it.

Either way, I didn't mean to say that it was only counter-intuitive in perl.

I meant, the way perl forces you to do it is counter-intuitive.

But Perl doesn't require you to do it this way. Perl allows to put either the cause, or the effect to go first.

Abigail

A common usage is when you don't want the if statement to obscure the readability of the code:

print "DEBUG: foo is $x\n" if $config->{debug};
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is less distracting than:

if ($config->{debug}) { print "foo is $x\n"; }
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The above statement reads more like English. Also, you can have main-path code not be obscured by error-handling logic, similarly enhancing readability, but this time in the reverse kind of way:

reticulate_splines() unless llamas_roaming_in_strawberries()
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In the above example, we usually reticulate the splines (say 90% of the time), but in emergencies, we skip the statement.

If all languages read exactly like C, it would be boring.

do_something()
    if COND;
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buys me both that initial visual cue that the statement is qualified as well as the satisfaction of the simpler, less "noisy", flavor of "if".

Which part is more important? The conditional or the statement? In some cases its one, some cases the other. And if you really want the conditional in front then just write:

($CONDITION) && do_something();
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But usually you are more interested in what might happen than exactly why so that becomes

do_something() unless $exception;
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But sometime the conditional part really aught to go first:

open ... or die ....
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demerphq


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