The number of characters in a string:

examples/lc.pl

use strict;
use warnings;
use 5.010;

my $hi = 'HeLlo';
my $hebrew = 'שלום';
my $arabic = 'سلام';
my $smiley = '😃';
say $hi;
say $hebrew;
say $arabic;
say $smiley;

say lc $hi;
say lc $hebrew;
say lc $arabic;
say lc $smiley;

See also the explanation in String functions: length, lc, uc, index, substr.

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