pattern to look for, as defined by a POSIX regular expression. See the "Extended Regular Expressions" section of regex for details. See fixed, ignore.case and perl for how to use other types of matching: fixed, case insensitive and perl-compatible expressions.

string. References of the form 1, 2 will be replaced with the contents of the respective matched group (created by ()) within the pattern.

These functions build functions that take a single string argument and return a vector as a result.

make_str_replace builds a functions that replaces the strings according to the pattern and replacement arguments.

make_str_delete builds a functions that deletes the pattern from the string.

make_str_is builds a function that detects is the string is has a certain type of formatting.