Re: Differences between " " and ' '?

If there's no variables inside to be interpolated, the optimizer transforms double quotes to single quotes:

    #!/usr/bin/perl
    #testscript
    if($a eq "quackidiquack") {
    }

    if($a eq 'quackidiquack') {
    }
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Now let's see what the optimizer does:

    perl -MO=Deparse testscript
    if ($a eq 'quackidiquack') {
        ();
    }
    if ($a eq 'quackidiquack') {
        ();
    }
testscript syntax OK
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Comment on Re: Differences between " " and ' '? Select or Download Code

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Re^2: Differences between " " and ' '? by diotalevi (Canon) on Jul 31, 2005 at 05:06 UTC
Your conclusion is correct but your methods are dodgy. B::Deparse doesn't tell you anything about how things are compiled or executed internally and it can be incorrect or just misleading. For accuracy, use B::Concise or something else that shows you the compiled optree. B::Deparse attempts to produce some sensible perl code based on the optree but it isn't really an oracle and it isn't always right. Added B::Deparse is supposed to produce canonically correct output as a core goal and it does really well. It just isn't so perfect. It also won't tell you that '...' is internally the same thing as "...". (it is)	[reply]
Re^2: Differences between " " and ' '? by Ace128 (Hermit) on Jul 31, 2005 at 04:59 UTC
Hey, that "perl -MO=Deparse .. " is something new for me! Nice, and thanks! Good to know about... like in cases like this!	[reply]