A preamble on Ocaml packaging and Mac OS X

Although OCaml is available as binary packages for Mac OS X, the problem is that this kind of distribution cannot easily be complemented by various packages available from the Caml Hump (an Ocaml equivalent of CPAN for Perl).

This is fine as long as one only wants to experiment with the language.

Beyond this, any work involving some pragmatic issues such as database persistence or internationalization, needs to be based one way or another on the functionality offered by the standard packages provided by the Ocaml community.

An example of this is the Camomile library, which is the de-facto standard to handle Unicode characters in Ocaml,
yet is not included in the standard Ocaml distribution.

As opposed to Java, there is no simple way to drop a library (such as a jar file) in some agreed directory.
The current Ocaml ecosystem relies on a source based package being built, compiled, tested, and installed into the Ocaml environment, in a fashion similar to Perl 5. Depending on the specifics of a package and on version considerations, this could lead to some serious headache(s).

Most of this package installation work is already automated through the GODI system, in essence a packaging system similar to Perl 5's CPAN shell on UNIX systems (or the Perl Package Manager on Windows).

My next post will cover some steps I went through on my Mac in order to complete the installation of GODI and of some packages required by my home project.

Suffice to say that GODI relies on more than just the default OS X functions. As highlighted in the high level view of my setup below,


a first prerequisite is that a version of the Xcode tools (including the gcc compiler) be installed on the OS X environment. This will allow GODI to compile the Ocaml distribution (e.g. 3.10) that it includes.

Another prerequisite is that GODI itself and some packages it installs, might rely on additional programs or tools not directly included into the Mac OS X environment or Xcode itself. This is where Fink can assist. Examples of such additional programs / tools provided through Fink:
- the PostgreSQL 8.0 database package
- the GNU Make utility

This overview was a needed preamble before diving into more technical matters in forthcoming posts.

Cheers

As a footnote: a more thorough coverage of possible options for Ocaml on Mac OS X, is available here.

Comments

Post a Comment

Popular posts from this blog

A possible solution for using the janus interface on MacOS with docker

 Experimenting with the Janus module on docker Janus is a new development that comes with swi-prolog version 9:  janus documentation Having attempted to run the example in the above link, I tried the following steps to install and use the spacy python package: pip install spacy docker run -it --rm --network host -v $(pwd):/opt/janus\ -v /path/to/python3.11/site-packages:/opt/python\ swipl ?- consult('/opt/janus/test_janus.pl'). ?- py_add_lib_dir('/opt/python'). ?- noun("This is a sentence.", Noun). ERROR: Python 'ImportError': ERROR: Error importing numpy: you should not try to import numpy from its source directory; please exit the numpy source tree, and relaunch your python interpreter from there. ERROR: Python stack: ERROR: File "/opt/python/spacy/__init__.py", line 6, in module ERROR: from .er...
Read more

Meaningful Xml Diffs with SWI-Prolog

Introduction Building on the previous article I wrote on using the SWI Prolog Xpath predicate for analyzing Xml Node Set relationships, I now describe a way to produce a tree oriented diff based on similar techniques. The goal of such a diff is to identify objects of 2 Xml trees which differ by a given sub-node. In a sense is that diff not a fully general diff, as it focuses on 2 or 3 levels: object sub-or-descendant node resp. property when required, property of the sub-or-descendant node specified by the user, within the Xml tree structure. Another important goal of this diff is to be able to accommodate a different ordering of these objects in the Xml structure, which is normally a constraint which most editors or developer tools can’t cope with. In the following sections I will again use a similar fictitious tree example as in the precedent article. Resources for this article Prolog source code and XML examples are available on  [github] ...
Read more

Prolog DCG "distilled" - Part 3 - Capturing and assembling textual elements from rules

Image
Capturing and assembling textual elements from rules This article builds on the previous ones, featuring a small parser for Org Mode files. I use the Clocking feature of emacs to capture how long I work on specific tasks.  However from time to time,  I have to aggregate data over several files, on a monthly or yearly basis, and this is where the small tool described here can prove useful. The code and tests for this article may be found [ here ]. One of the tests may be run in SWI-Prolog with those steps:                ?- consult('/path/to/clocking_tool.pl').                true.             ?- test_parse_clock(Start, End, Elapsed).             Start = [2020-2-5, 16:6:0], End = [2020-2-5, 17:26:0], Elapsed = 1:20 ;             false. A version for Tau-Prolog can be found  [he...
Read more