The parsers library provides a number of subclasses of the
Alternative type class,
as well as lots of combinators useful for writing actual parsers.
What those classes like
Parsing and
CharParsing lack is the
ability to express certain efficient parser primitives like Attoparsec’s
takeWhile. To rectify for
this failing and enable more efficient parsers to be expressed, the present package input-parsers adds type classes
InputParsing and
InputCharParsing. The
common characteristic of almost all their methods is that their parse result has the same type as the parser input,
and is a prefix of the input.
The present package also exports the class
DeterministicParsing,
which provides a number of parser methods that are guaranteed to succeed with a single (typically longest possible)
result. This is most useful for writing the lexical layer of a parser, but it can help avoid ambiguities and
inefficiencies in general.
