Map-like class where .get(key) always result in defined value

Create an Err

Filter a list of classified arguments for flags with certain names

Determine flag prefix

Convert a multi-line string into an iterator of lines, with each line being prefixed

Create an Ok

Divide a list of classified arguments into two: one for flags with certain names, other for the rest

Create an object of single property

Convert a flag name to a flag argument

Convert a list of raw arguments to an iterator of classified arguments

Convert a multi-line string into an iterator of lines

Convert a multi-line string into an iterator of lines, with each line being prefixed

Divide a list into two, one where fn returns true, other where fn returns false