OCaml is a general purpose industrial-strength programming language with an emphasis on expressiveness and safety. Developed for more than 20 years at Inria it benefits from one of the most advanced type systems and supports functional, imperative and object-oriented styles of programming.

Pure OCaml regular expressions with:

1. Perl-style regular expressions (module Re_perl)

2. Posix extended regular expressions (module Re_posix)

3. Emacs-style regular expressions (module Re_emacs)

4. Shell-style file globbing (module Re_glob)

5. Compatibility layer for OCaml's built-in Str module (module Re_str)

Hmap provides heterogeneous value maps for OCaml. These maps bind keys to values with arbitrary types. Keys witness the type of the value they are bound to which allows adding and looking up bindings in a type safe manner.

Bos provides support for basic and robust interaction with the operating system in OCaml. It has functions to access the process environment, parse command line arguments, interact with the file system and run command line programs.

Part of the Jane Street's PPX rewriters collection.

An implementation inspired by Okasaki & Gill's paper 'Fast Mergeable Integer Maps.'

Markup.ml provides an HTML parser and an XML parser. The parsers are wrapped in a simple interface: they are functions that transform byte streams to parsing signal streams. Streams can be manipulated in various ways, such as processing by fold, filter, and map, assembly into DOM tree structures, or serialization back to HTML or XML.

Both parsers are based on their respective standards. The HTML parser, in particular, is based on the state machines defined in HTML5.

The parsers are error-recovering by default, and accept fragments. This makes it very easy to get a best-effort parse of some input. The parsers can, however, be easily configured to be strict, and to accept only full documents.

Apart from this, the parsers are streaming (do not build up a document in memory), non-blocking (can be used with threading libraries), lazy (do not consume input unless the signal stream is being read), and process the input in a single pass. They automatically detect the character encoding of the input stream, and convert everything to UTF-8.

Libraries for creating shared memory producer/consumer rings. The rings follow the Xen ABI and may be used to create or implement Xen virtual devices.

Eio_linux provides a Linux io-uring backend for Ocaml Eio APIs, plus a low-level API that can be used directly (in non-portable code).

The "findlib" library provides a scheme to manage reusable software components (packages), and includes tools that support this scheme. Packages are collections of OCaml modules for which metainformation can be stored. The packages are kept in the file system hierarchy, but with strict directory structure. The library contains functions to look the directory up that stores a package, to query metainformation about a package, and to retrieve dependency information about multiple packages. There is also a tool that allows the user to enter queries on the command-line. In order to simplify compilation and linkage, there are new frontends of the various OCaml compilers that can directly deal with packages.

Uses the new result type defined in OCaml >= 4.03 while staying compatible with older version of OCaml should use the Result module defined in this library.

A ppx rewriter that inlines reverse application operators |> and |!.

These libraries provides access to low-level compiler interfaces and the standard higher-level merlin protocol.

Unix-related dependencies for things like system calls and threads. Using these, it hooks the Async_kernel scheduler up to either epoll or select, depending on availability, and manages a thread pool that blocking system calls run in.

Gen implements iterators of OCaml, that are both restartable and consumable.

Library to provide pure OCaml functions to manipulate real file (POSIX like) and filename.

Lwt provides typed, composable cooperative threads. These make it easy to run normally-blocking I/O operations concurrently in a single process. Also, in many cases, Lwt threads can interact without the need for locks or other synchronization primitives.

Core is an alternative to the OCaml standard library.

Core_kernel is the system-independent part of Core. It is aimed for cases when the full Core is not available, such as in Javascript.

This package contains a compatibility library for Stdlib.Bigarray in OCaml.

Dune is a build system for OCaml. It provides a consistent experience and takes care of the low-level details of OCaml compilation. Descriptions of projects, libraries and executables are provided in dune files following an s-expression syntax.

This library implements portable support for an operating system timesource that is compatible with the MirageOS library interfaces. It implements an MCLOCK module that represents a monotonic timesource since an arbitrary point, and PCLOCK which counts time since the Unix epoch.

Dose3 is a framework made of several OCaml libraries for managing distribution packages and their dependencies. Though not tied to any particular distribution, dose3 constitutes a pool of libraries which enable analyzing packages coming from various distributions. Besides basic functionalities for querying and setting package properties, dose3 also implements algorithms for solving more complex problems such as monitoring package evolutions, correct and complete dependency resolution and repository-wide uninstallability checks.

This package provides two union-find data structure implementations for OCaml. Both implementations are based on disjoint sets forests, with path compression and linking-by-rank, so as to guarantee good asymptotic complexity: every operation requires a quasi-constant number of accesses to the store.

This package is an OCaml library to parse and generate the YAML file format. It is intended to be interoperable with the Ezjsonm JSON handling library, if the simple common subset of Yaml is used. Anchors and other advanced Yaml features are not implemented in the JSON compatibility layer.