How do is the case of a string identified?

For a letter you can use the regex /\p{Lu}/ which matches upper case letters, \p{Ll} for lower case, and \p{Lt} for title case. Also remember that many characters don't have the lower case/upper case distinction (like digits, and letters from many different writing systems).

A crude way would also be a test like lc($x) eq $x

Perl 6 - links to (nearly) everything that is Perl 6.

In reply to Re: Reversing string case by moritz
in thread Reversing string case by perlpal

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