Matts showed me a clever way to do it the other day. I thought it was beautiful:

  $INC{ 'bytes.pm' }++ if $] < 5.006
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Once that's in %INC, calls to "use bytes" do nothing, apparently

Cool.

I had previously convinced myself that because BEGIN requires a block, I couldn't fake out 'use warnings' for people who don't have it but then I realized this works fine:

BEGIN {
    if(  eval { require warnings }  ) {
        warnings->import();
    } else {
        $^W= 1;
    }
}
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because the pragmas already expect to be inside of a (invisible) block and so apply themselves to one block further out.

I like this method because it allows the user to install a back-ported warnings.pm or bytes.pm or whatever and use it if they want to and I don't have to trust my knowledge of when the module was added. (:

Anyway, it is another way to do it.

                - tye

Thanks Tye! Applying this to "use bytes," am I correct that your solution is basically the same approach as the one I originally suggested? In other words, isn't this...
BEGIN {
    if(  eval { require bytes }  ) {
        bytes->import();
    }
}
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...pretty much the same as this:
BEGIN {
eval {require bytes; import bytes; 1}
}
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I'm a bit new to trying to import modules and pragmas outside of the regular "use" function, so I'm just trying to be sure that I understand the difference, if any.

Thanks! Josh

Hey, interesting! So, the idea would be to do it like this?
BEGIN {
$INC{ 'bytes.pm' }++ if $] < 5.006
use bytes;
}
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This will cause 5.005 and below to ignore "use bytes" and cause 5.6+ to use the bytes pragma as usual? Nifty!

Thanks for the help, Josh

$bytes = pack "C0a*", $bytes_or_utf8;
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