Letter Casing in Perl 5
Letter casing functions are available in the core language and have Unicode semantics for character strings but ASCII semantics for byte strings.
$lowercase = lc $str; $uppercase = uc $str; $titlecase = ucfirst $str; use v5.16; $casefold = fc $str;
fc function was added in Perl 5.16 and requires
use v5.16 or
use feature 'fc'. The CPAN module
Unicode::CaseFold provides the
function for Perl 5.8.1 or greater.
use Unicode::CaseFold; $casefold = fc $str;