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= README =
OCaml is an implementation of the ML language, based on the Caml Light
dialect extended with a complete class-based object system and a powerful
module system in the style of Standard ML.
OCaml comprises two compilers. One generates bytecode which is then
interpreted by a C program. This compiler runs quickly, generates compact
code with moderate memory requirements, and is portable to essentially any
32 or 64 bit Unix platform. Performance of generated programs is quite good
for a bytecoded implementation. This compiler can be used either as a
standalone, batch-oriented compiler that produces standalone programs, or as
an interactive, toplevel-based system.
The other compiler generates high-performance native code for a number of
processors. Compilation takes longer and generates bigger code, but the
generated programs deliver excellent performance, while retaining the
moderate memory requirements of the bytecode compiler. The native-code
compiler currently runs on the following platforms:
Tier 1 (actively used and maintained by the core OCaml team):
AMD64 (Opteron):: Linux, OS X, MS Windows
IA32 (Pentium):: Linux, FreeBSD, OS X, MS Windows
PowerPC:: Linux, OS X
Tier 2 (maintained when possible, with help from users):
AMD64:: FreeBSD, OpenBSD, NetBSD
IA32 (Pentium):: NetBSD, OpenBSD, Solaris 9
Other operating systems for the processors above have not been tested, but
the compiler may work under other operating systems with little work.
Before the introduction of objects, OCaml was known as Caml Special Light.
OCaml is almost upwards compatible with Caml Special Light, except for a few
additional reserved keywords that have forced some renaming of standard
All files marked "Copyright INRIA" in this distribution are copyright 1996,
1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,
2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016 Institut National de
Recherche en Informatique et en Automatique (INRIA) and distributed under
the conditions stated in file LICENSE.
See the file link:INSTALL.adoc for installation instructions on
machines running Unix, Linux, OS X and Cygwin. For native Microsoft
Windows, see link:README.win32.adoc.
The OCaml manual is distributed in HTML, PDF, Postscript, DVI, and Emacs
Info files. It is available at
The community also maintains the Web site http://ocaml.org, with tutorials
and other useful information for OCaml users.
The complete OCaml distribution can be accessed at
== Keeping in Touch with the Caml Community
There exists a mailing list of users of the OCaml implementations developed
at INRIA. The purpose of this list is to share experience, exchange ideas
(and even code), and report on applications of the OCaml language. Messages
can be written in English or in French. The list has more than 1000
Messages to the list should be sent to:
You can subscribe to this list via the Web interface at
Archives of the list are available on the Web site above.
The Usenet news `groups comp.lang.ml` and `comp.lang.functional` also
contains discussions about the ML family of programming languages, including
The IRC channel `#ocaml` on https://freenode.net/[Freenode] also has several
hundred users and welcomes questions.
The OCaml Community website is
== Bug Reports and User Feedback
Please report bugs using the Web interface to the bug-tracking system at
To be effective, bug reports should include a complete program (preferably
small) that exhibits the unexpected behavior, and the configuration you are
using (machine type, etc).
You can also contact the implementors directly at mailto:email@example.com.
For information on contributing to OCaml, see link:HACKING.adoc and