I do a lot of conditional testing, such as: 
        if     ($x == 1) { $abc = 1 }
        elsif ($x == 2) { $def = 1 }
        elsif ($x == 3) { $xyz = 1 }
        else                  { $nothing = 1 }

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but in reading Prog. Perl (p. 125) I see this could send me to the confessional. So, I tried: 
    SWITCH: {
        if ($x == 1)    { $abc = 1; last SWITCH; };
        if ($x == 2)    { $def = 1; last SWITCH; };
        if ($x == 3)    { $xyz = 1; last SWITCH; };
        $nothing = 1;
    }

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or 
    SWITCH: for ($x) {
        if (1)    { $abc = 1; last SWITCH; };
        if (2)    { $def = 1; last SWITCH; };
        if (3)    { $xyz = 1; last SWITCH; };
        $nothing = 1;
    }

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Sure it looks nicer, but in speed tests, depending on how $x is set, this later structure always slower, and in some cases significantly.

My question, what am I missing here? The if/else structure actually looks cleaner to me and if it's faster...

Thanks, monks of greater XP.

bradcathey

In reply to Use of SWITCH vs IF ELSE in speed and readability by bradcathey

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