====== Regular Expressions ======

===== Common regexes =====
^ purpose/match/validates ^ Regex |
| FQDN[(fully qualified domain name)][(from http://blog.gnukai.com/2010/06/fqdn-regular-expression/ which references [[https://datatracker.ietf.org/doc/html/rfc1035|RFC1035]])] | ''%%(?=^.{1,254}$)(^(?:(?!\d|-)[a-zA-Z0-9\-]{1,63}(?<!-)\.?)+(?:[a-zA-Z]{2,})$)%%'' |

===== online tools =====
  * [[https://regexr.com/|Regexr]] – evaluates and explains regular expressions
  * [[https://www.regexpal.com/|Regexpal]] – evaluates regexes
  * [[https://regex101.com/|Regex101]] – online RegEx IDE
  * [[https://regexcrossword.com/|Regex Crossword]] – game to learn regular expressions