Perl function.
lc [EXPR]
Returns a lowercase version of its argument, or $_ if given no arguments. Note that . has a higher precedence than lc, so something like $foo = lc "ABC . "DEF" will yield "abcdef" instead of "abcDEF". I mention this only because I seem to do it every time I use lc.
lc $foo is equivalent to "\L$foo".
For example:
sub word_cap {
$string = shift;
$string =~ s/\b(\w+)\b/ucfirst lc $1/gie;
return $string;
}
See also lcfirst, uc, and ucfirst, or Perl for the full function list.