A list of character vectors for alternate specification.
sep
Regex for separating components of complete regex.
Defaults to "an optional space or hyphen".
Value
A string containing a regex.
Each element in the vectors are pasted together, separated by the
sep value. Those character vectors are then preceded by "^"
(regex for 'start of string'() and followed by "$" (regex for end
of string). Finally, the regexes are collapsed with "|" (regex for
'or').