SingleValueConverter

Takes a list of arguments to all option invocations: for example, "-a 1 2 -a 3 4 5" would produce List(("a",List(1,2)),("a",List(3,4,5))).

• parse returns Left, if there was an error while parsing.

• if no option was found, it returns Right(None).

• if option was found, it returns Right(...).

Transformation of argument name to argument definition in help.

Map the converter to another value. This method is different from .map because it can return an error (without resorting to exceptions, returning Left(msg)) or can filter out unsupported values (by returning Right(None)).

Maps the converter to another value:

intConverter.map(_+2) // and you get a "biased converter"

Type of parsed argument list.