This provides String instances for RegexMaker and RegexLike based on Text.Regex.Posix.Wrap, and a (RegexContextRegexStringString) instance.
To use these instance, you would normally import Text.Regex.Posix. You only need to import this module to use the medium level API of the compile, regexec, and execute functions. All of these report error by returning Left values instead of undefined or error or fail.