This library provides the natural numbers for Haskell.

This package provides first class functional references. In addition to the usual operations of getting, setting and composition, plus integration with the state monad, lens families provide some unique features:

• Polymorphic updating

• Traversals

• Cast projection functions to read-only lenses

• Cast toList functions to read-only traversals

• Cast semantic editor combinators to modify-only traversals

For optimal first-class support use the lens-family package with rank 2/rank N polymorphism. Lens.Family.Clone allows for first-class support of lenses and traversals for those who require Haskell 98.

Expose Haskell objects to Lua with an object oriented interface.

This package provides datatypes to construct Free monads, Free monad transformers, and useful instances. In addition it provides the constructs to avoid quadratic complexity of left associative bind, as explained in:

• Janis Voigtlander, Asymptotic Improvement of Computations over Free Monads, MPC'08

This package provides a configuration management library for programs and daemons. The features include:

1. Automatic, dynamic reloading in response to modifications to configuration files.

2. A simple, but flexible, configuration language, supporting several of the most commonly needed types of data, along with interpolation of strings from the configuration or the system environment (e.g. $(HOME)).

3. Subscription-based notification of changes to configuration properties.

4. An import directive allows the configuration of a complex application to be split across several smaller files, or common configuration data to be shared across several applications.

This package provides distributive functors for Haskell. Dual to Traversable.

This package provides a simple compatibility shim that lets you work with both binary and cereal with one chunk of serialization code.

This package provides bindings to the ALSA simple mixer API.

This module provides set and multiset operations on ordered lists.

This package provides a pure Haskell client library for the Music Player Daemon.

This package provides a simple interface for building .dot graph files, for input into the dot and graphviz tools. It includes a monadic interface for building graphs.

This package provides a type called @DMap@ which generalizes @Data.Map.Map@, allowing keys to specify the type of value that can be associated with them.

A cross-platform library with functions for adjusting code pages on Windows. On all other operating systems, the library does nothing.

This library implements the GHC API. It is like the compiler-provided ghc package, but it can be loaded on many compiler versions.

This package provides semigroups for Haskell. In mathematics, a semigroup is an algebraic structure consisting of a set together with an associative binary operation. A semigroup generalizes a monoid in that there might not exist an identity element. It also (originally) generalized a group (a monoid with all inverses) to a type where every element did not have to have an inverse, thus the name semigroup.

This library lets you derive automatically Haskell functions that let you query each endpoint of a <http://hackage.haskell.org/package/servant servant> webservice. . See <http://docs.servant.dev/en/stable/tutorial/Client.html the client section of the tutorial>. . <https://github.com/haskell-servant/servant/blob/master/servant-client/CHANGELOG.md CHANGELOG>.

A Haskell 98 logically uninhabited data type, used to indicate that a given term should not exist.

This Haskell package provides a lens library, just like ghc-lens, but smaller. It provides essential lenses and traversals (like _1 and _Just), as well as ones which are simply nice to have (like each, at, and ix), and some combinators (like failing and singular), but everything else is stripped. As the result, this package has no dependencies.

This package provides a string interpolation library for Haskell.

This package provides a canonical anonymous 1-tuple type missing from Haskell for attaching typeclass instances.

There is also the OneTuple package which by using a boxed data-type provides a 1-tuple type which has laziness properties which are more faithful to the ones of Haskell's native tuples; whereas the primary purpose of Only is to provide the traditionally so named type-wrapper for attaching typeclass instances.

This package provides a small, efficient, and portable regex library for Perl 5 compatible regular expressions. The PCRE library is a set of functions that implement regular expression pattern matching using the same syntax and semantics as Perl 5.

This package provides the ShortText type which is suitable for keeping many short strings in memory. This is similar to how ShortByteString relates to ByteString.

The main difference between Text and ShortText is that ShortText uses UTF-8 instead of UTF-16 internally and also doesn't support zero-copy slicing (thereby saving 2 words). Consequently, the memory footprint of a (boxed) ShortText value is 4 words (2 words when unboxed) plus the length of the UTF-8 encoded payload.

The Union/Find algorithm implements these operations in (effectively) constant-time:

1. Check whether two elements are in the same equivalence class.

2. Create a union of two equivalence classes.

3. Look up the descriptor of the equivalence class.

This package provides a backwards compatibility layer for Template Haskell newer than 2.8.