This expression gives me the hostname for a given schema

This regex matches only when all the following are true: password must contain 1 number (0-9) password must contain 1 uppercase letters password must contain 1 lowercase letters password must contain 1 non-alpha numeric number...

verify if a string can be use in a username pattern for my project

break the code to first opening parenthesis and then closing use the groups individually not entirely . This is 40% correct online pattern but mixing it with first open then close groups in two different matches result in 100% success

only valid chars

It checks whether the Github Profile URL is valid.