I18N::LangTags::List implements the name() function that takes a language tag and returns its best attempt at an English name for it. If name() doesn't understand the language tag, it returns undef.

For example:

#!/usr/local/bin/perl -w
use I18N::LangTags::List;
 
my $tag = 'en-CA';
print "What is this tag aboot? ",
	    I18N::LangTags::List::name($tag),

"\n";