in reply to Simple Switch statement

A switch statement is basically a dispatch table. I would use something like that. Other options would include something like: 
for ($val)
{
    /^1$/       && do { do_something };
    /^abc$/     && do { do_something_else };
    /^\d{2,4}$/ && do { do_something_further };
}

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This is straight out of the Camel.

------
We are the carpenters and bricklayers of the Information Age.

The idea is a little like C++ templates, except not quite so brain-meltingly complicated. -- TheDamian, Exegesis 6

Please remember that I'm crufty and crochety. All opinions are purely mine and all code is untested, unless otherwise specified.

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Re: Re: Simple Switch statement
by bradcathey (Prior) on Sep 13, 2003 at 01:28 UTC
    I normally do just as dragonchild suggests, which is indeed right out of holy writ. However, don't be too quick to give up the old if/then/else. While maybe not as clean looking or as cool, the venerable standby can be about 2x as fast, though, admittedly, usually not noticeable unless you are testing thousands of conditions :-)

    Switch/case is one of the RARE features I miss from traditionally frowned upon javascript.
[reply]
      I agree with what bradcathey said about if/then/else. Also on testing of simple strings/values. The mundane
      if ($a eq "simple value")
{
  ...
}

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      runs faster than
      if ($a =~ /^simple value$/)
{
  ...
}

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      The point is to avoid using regular expressions on simple string testing. Any bit of speed increase in perl is good, especially when it has to be evaluated countless times.

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[select]

        Ah, but why not:

        for($switch_me) {
    /bob/   && do { print "Got 'bob'!\n"; break };
    /frnak/ && do { print "Got 'frnak'!\n"; break };
    $_ == 1 && do { print "Got 1!\n"; break };

    print "Got nuttin'!\n";
}

        [download]

        You can have your cake AND eat it too.

        Alakaboo

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