Alias of
Pattern[/(?x) ^ ( (?= [a-z0-9._-]{2,255} ) ( (?= [a-z0-9_-]{1,63} \. ) _ [a-z0-9]+ ( - [a-z0-9]+ )* \. )+ _ [a-z]{2,62} ) $/]
# File 'types/domain.pp', line 2