Library should use the module Gettext.Library. It doesn't need any real implementation
of ocaml-gettext. By this way, you can let the library user choose the most appropriate ocaml-gettext
implementation. This point is essential : a library could be used as well in a GUI program or in short run
command line program. These two examples don't require the same kind of implementation at all: GUI program
loads most of their translated strings, command line program only use one among them. So by using the module
Gettext.Library framework, you don't restrict programs to use one particular implementation
of ocaml-gettext.
The library should define, using the functor Init provided:
his textdomain through the textdomain value,
his dependencies through the dependencies value,
if needed his charset and directory binding ( but it is not recommended to do so ).
After having instantiated the module Gettext.Library with the appropriate Init,
you should use the function provided :
You must keep the function name s_, f_, sn_ and fn_.
The extraction of translatable strings matches these names. If you don't keep it, the extraction of translatable strings
will fail.
Example 3.5. library.ml
(**************************************************************************)
(* Ocaml-gettext : example code *)
(* *)
(* Copyright (C) 2003, 2004, 2005 Sylvain Le Gall <sylvain@le-gall.net> *)
(* *)
(* You can redistribute this library and/or modify it under the terms of *)
(* the GNU LGPL v2.1 with the OCaml static compilation exception. *)
(* *)
(* Contact: sylvain@le-gall.net *)
(**************************************************************************)
open LibraryGettext.Gettext;;
(* Give access to the init of LibraryGettext *)
let init =
Gettext.init
;;
(* Example function *)
let library_only_function () =
(* Two simple examples : singular translation *)
print_endline (s_ "Hello world !");
Printf.printf (f_ "Hello %s !\n") "world";
(* More complicated : plural translation, using strings *)
print_endline (
(sn_ "There is " "There are " 2)
^(string_of_int 2)
^(sn_ "plate." "plates." 2)
);
(* More simple forms of plural translation, using printf *)
Printf.printf (fn_ "There is %d plate.\n" "There are %d plates.\n" 2) 2
;;
(* Another example function : used by program.ml *)
let hello_you name =
Printf.printf (f_ "Hello %s\n") name
;;
Example 3.6. libraryGettext.ml
(**************************************************************************) (* Ocaml-gettext : example code *) (* *) (* Copyright (C) 2003, 2004, 2005 Sylvain Le Gall <sylvain@le-gall.net> *) (* *) (* You can redistribute this library and/or modify it under the terms of *) (* the GNU LGPL v2.1 with the OCaml static compilation exception. *) (* *) (* Contact: sylvain@le-gall.net *) (**************************************************************************) (* Create the module Gettext, using the textdomain "mydomain" *) module Gettext = Gettext.Library(struct let textdomain = "mydomain" let codeset = None let dir = None let dependencies = Gettext.init end) ;;
All the calls to translation functions, use the textdomain provided in Init.
The only constraint when using ocaml-gettext in your library is to provide an access to the value
Gettext.Library.init. This value is used as dependencies for other libraries and
programs that depend on it. For example, since you use the library ocaml-gettext, your primary dependency
is the function init provided in the top level ( the function Gettext.string_of_exception
is localised ).
If you distribute your library, don't forget to mention that ocaml-gettext will only be able to translate the string defined in your library, if and only if the MO file build with is also installed. If not installed ocaml-gettext is useless.
[6]
Strings which should be used by Printf function are checked to be sure
that the returned strings are equivalent to the provided English string. In particular, every
"%"-symbol should be the same in the provided string and the returned string. If not,
it is the untranslated string which is returned.