Regular Expressions (REGEX)

Regex is a useful tool that settle has support for, because it provides
wildcards and patterns which allow matching multiple strings. See this regular
expression specification for
all supported patterns. But here are a few of the most useful characters you're
going to use:

  - . - match any single character
  - * - match the previous character zero or more times
  - + - match the previous character one or more times

If you wanted to match a literal ., * or +, you'd have to escape them with
a backslash: \., \* and \+ respectively.

Here are some examples:

  - .* matches anything, even empty strings
  - f+ matches the character f one or more times
  - .*foo.* matches any string containing the word foo
