$r =~ s[([a-zA-Z])][$1 lt '[' ? 'U' : 'L']ge;;

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But this will be vastly more efficient:

$r =~ tr[A-Z][U];
$r =~ tr[a-z][L];

[download]
With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: change [A-Z] to U, [a-z] to L with one regex? by BrowserUk
in thread change [A-Z] to U, [a-z] to L with one regex? by Doctrin

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