What is Regex? Regex (or regular expressions, formally) are a way to write out regular grammars. For those who are interested, you could find a little more info on regular grammars and the theory behind regular expressions here (https://www.tutorialspoint.com/automata_theory/regular_expressions.htm). And for those of you who've used regex before, you'd know that every regex engine has its own syntax. This bot uses the rust regex library, which has its syntax documented here (https://docs.rs/regex/0.2.10/regex/)