#! perl -slw
use strict;
my %validLanguages = (
       "de" => "german",
       "en" => "english",
       "es" => "spanish",
       "fr" => "french",
       "it" => "italian",
       "ja" => "japanise",
       "ko" => "korean",
        "ru" => "russian",
       "sv" => "WHATS THIS",
        "zh" => "WHATS THIS",
        "zh_TW" => "WHATS THIS"
);

my $re_langs = join'|', keys %validLanguages;
$re_langs = qr[\s*(?:$re_langs)\s*(?:,|$)]io;

sub isOnlyLangs{
	my ($string) = @_;
	$string =~ s[$re_langs][]g;
	$string =~ m[^\s*$];
}

sub isOnlyLangs_{ (my $s = $_[0]) =~ s[$re_langs][]g; !$s; }

print isOnlyLangs($_) ? 'Passed : ' : 'Failed : ', "'$_'"
	for
	'de, en, fr, ja',
	' de  , en  , fr  , ja ,  ',
	'monkish fr, en',
	'monkish, fr, en',
	'FR',
	'Fr',
	'fr en',
	'fr ,  en,',
	'zh_tw';