Hello
Here is the latest Caml Weekly News, for the week of March 20 to 27, 2007.
New version 1.13 of ledit. Ledit is a text editor allowing to edit lines while using an interactive command (e.g. the ocaml toplevel). Change: Added option -u to allow using utf-8 encoding. http://pauillac.inria.fr/~ddr/ledit/ New version 1.00 of mlrogue. MLrogue is a clone of rogue, a game of the 80ies running in a terminal 24x80 (e.g. an xterm). Change: minor fixes and improvements. Work well after months of testing. http://pauillac.inria.fr/~ddr/mlrogue/
A one-year INRIA post-doctoral position is available: Title: Generation of construction functions guaranteeing algebraic invariants on concrete data types Aim: Although concrete data types are very useful in defining complex data structures, they are not always sufficient to adequately specify the data structures required by some algorithms. Often, only a subset of the concrete data type is in fact used since some invariants between the components are mandatory to ensure the correctness of the program. Now, many invariants can be described by using some equational theory. For instance, a sorted list is a particular representative of the equivalence class of lists modulo commutativity. The usual way to solve this problem is to use abstract data types or, better, private data types if one does not want to lose the ability of doing pattern matching. We propose to study the automatic generation of certified construction functions guaranteeing algebraic invariants on concrete data types, and develop an extension of OCaml with relational data types, that is, data types with invariants described by user defined equations. More information and online application on: http://www.talentsplace.com/syndication1/inria/frpostdoc/details.html?id=PGTFK026203F3VBQB6G68LONZ&LOV5=4508&LOV6=4514&LG=FR&Resultsperpage=20&nPostingID=1155&nPostingTargetID=3197&option=52&sort=DESC&nDepartmentID=19 Competences and profile: The position involves research and development in the area of functional programming, rewriting theory (in particular Knuth-Bendix completion) and, possibly, interactive theorem proving (experience with a proof assistant such as Coq is welcome). Speaking french is not necessary. Requirements: Candidates are required to hold a PhD degree between May 2006 and June 2007. Salary: the monthly gross salary is approx. EUR 2,150. Environment: - laboratory: LORIA (http://www.loria.fr/) - team: Protheo (http://protheo.loria.fr/) - project: Quotient (http://quotient.loria.fr/) - location: Nancy, in the East of France is at 1:30 from Paris by tren, 1:30 from Luxembourg airport by car, and 1:30 from Germany and Belgium. Application deadline: 1st July 2007. Contact: Frederic Blanqui (http://www.loria.fr/~blanqui/) More information about INRIA post-doctoral positions: http://www.inria.fr/travailler/opportunites/postdoc/postdoc.en.html
I just created http://cocan.org/comparisons (thanks to Christophe Raffalli for allowing me to reuse http://www.lama.univ-savoie.fr/~raffalli/ocaml-parsing.html) It seems to me that a wiki is more suitable than a mailing list for this kind of information sharing. Feel free to - add you wishes on the list of needs to compare - contribute to the pages (even small additions and corrections) - argue that wikipedia would be better for this (and do the migration)
> Is there some documentation or at least a tutorial for how to setup
> ocamlbuild in order to build a lib<name>.a file from a bunch of *.c, *.C,
> and *.h files?
Roughly...
$ cat libfoo.clib
foo1.o
bar2.o
..
$ ocamlbuild libfoo.a
> And after having done that, how to tell ocamlbuild that some ocmal-program
> which is build depends on lib<name>.a.
$ cat _tags
<myocamprog.{byte,native}: use_foo
$ cat myocamlbuild.ml
open Ocamlbuild_plugin;;
open Command;;
dispatch begin function
| After_rules ->
flag ["ocaml"; "link"; "use_foo"]
(S[A"-cc"; A"g++"; A"-ccopt"; A"-Lfoo"; A"-custom";
A"-cclib"; A"-Ifoo"]);
dep ["ocaml"; "link"; "use_foo") ["libfoo.a"]
end;;
Some `flag' declaration might be useful in order to tweak the C/C++ compilation.
> I would like you or anyone knowledgeable to translate one significant
> syntax extension. You know, some kind of Rosetta stone. You can take
> Markus' sexp syntax extension or ioxml if you prefer, it won't be much
> different.
Here is your rosetta stone :)
I translated pa_json_static.ml.
To highlight a little the changes in the AST,
I want to show an input snippet and two translations:
For the old camlp4 it was:
| Object l ->
let ml = List.map (fun x -> (x.field_caml_name,
convert x.field_type)) l in
<:ctyp< < $list:ml$ > >>
The type of `ml' is (string * ctyp) list. The concept of quotations is
to get concrete syntax for abstract terms and then avoid to learn all
constructors and types. Alas for some of them you have to know the type.
In the new version you can express any term (except one) by concrete syntax.
The closest version is:
| Object l ->
let ml = List.map (fun x ->
<:ctyp< $lid:x.field_caml_name$ : $convert x.field_type$ >>) l in
<:ctyp< < $list:ml$ > >>
Here one doesn't know if methods declarations are a pair or something else and
we don't care. Since one knows the syntax << method_name : method_type >>.
At this place the list antiquotation $list:ml$ is a sugar for
$Ast.tySem_of_list ml$.
By changing a little more the code one can use something closer to the
object syntax.
| Object l ->
let ml = List.fold_right (fun x acc ->
<:ctyp< $lid:x.field_caml_name$ : $convert x.field_type$ ; $acc$ >>)
l <:ctyp<>> in
<:ctyp< < $ml$ > >>
The general syntax of object types (omiting `..' for the row variable) is
< meth1 : type1 ; ... ; methN : typeN > then one can avoid to construct a list
(since map is a fold_right with `::') and then call a function that destruct it.
Another thing to point out is the use of the nil type <:ctyp<>> that is quite
useful to start the folding.
In this translation I used both styles depending of the context.
The patch:
http://gallium.inria.fr/~pouillar/pub/camlp4/rosetta/pa_json_static/pa_json_static.patch
The new version (compiles with camlp4orf):
http://gallium.inria.fr/~pouillar/pub/camlp4/rosetta/pa_json_static/pa_json_static.ml
Here is a quick trick to help you read this CWN if you are viewing it using vim (version 6 or greater).
:set foldmethod=expr
:set foldexpr=getline(v:lnum)=~'^=\\{78}$'?'<1':1
zM
If you know of a better way, please let me know.
If you happen to miss a CWN, you can send me a message and I'll mail it to you, or go take a look at the archive or the RSS feed of the archives.
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