This regular expression is designed to work with character-delimited strings, and provides a means to specify the index of delimiter occurrence at which content is extracted.

usefull if you want to return (N) words instead of (N) chars

simple ip:port or host:port parser capturing ip or host and port, usually used for proxy lists

Tests a floating point number

It accepts phone numbers of the form 0XX XXX XX XX (stylized here, it doesn't really accept spaces). Also, it can detect the international area code (e.g. +41 OR 0041 for Switzerland). It's not a good idea to rely on the groups (because they do not work for this reason. At ALL.

Search group "link=>text" in tags "a"

Match all certificate in a chain from a OpenSSL s_client output. Need for this come from a script that should be able to verify the root CA of a URL.

valida el formato del registro federal de contribuyentes de México.

/** this regex should match most cases where the user forgets to put an operator somewhere and add an OR, it still does not handle nested square brackets but those are invalid anyways this page has an explanation https://regex101.com/r/fF7wO1/2 * the way this regex grabs conflicting matches is b...

Email validator from http://haacked.com/archive/2007/08/21/i-knew-how-to-validate-an-email-address-until-i.aspx/

#starts with abc, has 123 and ends with xyz abc123xyz