megaparsec

# Megaparsec

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* [Features](#features)
    * [Core features](#core-features)
    * [Error messages](#error-messages)
    * [External lexers](#external-lexers)
    * [Character and binary parsing](#character-and-binary-parsing)
    * [Lexer](#lexer)
* [Documentation](#documentation)
* [Tutorials](#tutorials)
* [Performance](#performance)
* [Comparison with other solutions](#comparison-with-other-solutions)
    * [Megaparsec vs Attoparsec](#megaparsec-vs-attoparsec)
    * [Megaparsec vs Parsec](#megaparsec-vs-parsec)
    * [Megaparsec vs Trifecta](#megaparsec-vs-trifecta)
    * [Megaparsec vs Earley](#megaparsec-vs-earley)
    * [Megaparsec vs Flatparse](#megaparsec-vs-flatparse)
* [Related packages](#related-packages)
* [Prominent projects that use Megaparsec](#prominent-projects-that-use-megaparsec)
* [Links to announcements and blog posts](#links-to-announcements-and-blog-posts)
* [Contribution](#contribution)
* [License](#license)

This is an industrial-strength monadic parser combinator library. Megaparsec
is a feature-rich package that strikes a nice balance between speed,
flexibility, and the quality of parse errors.

## Features

The project provides flexible solutions for common parsing needs. This
section describes them briefly. If you're looking for comprehensive
documentation, see the [section about documentation](#documentation).

### Core features

The package is built around `MonadParsec`, an MTL-style type class. Most
features work with all instances of `MonadParsec`. You can achieve various
effects by combining monad transformers, i.e. by building a monadic stack.
Since the common monad transformers like `WriterT`, `StateT`, and `ReaderT`
are instances of the `MonadParsec` type class, you can also wrap `ParsecT`
*in* these monads, achieving, for example, backtracking state.

`ParsecT` is also an instance of many type classes itself. The most useful
ones are `Monad`, `Applicative`, `Alternative`, and `MonadParsec`.

Megaparsec includes all functionality that is typically available in
Parsec-like libraries and also features some special combinators:

* `parseError` allows us to end parsing and report an arbitrary parse error.
* `withRecovery` can be used to recover from parse errors “on the fly” and
  continue parsing. Once parsing is finished, the collected parse errors may
  be reported or ignored altogether.
* `