Module Topfind

module Topfind: sig .. end

Load packages from toploops and scripts

The Topfind module is part of the findlib package. The module depends on the presence of a toploop. When building a toploop, it is automatically linked in if "findlib" is linked in, e.g.

 ocamlfind ocamlmktop ...options... -package findlib -linkpkg

When the platform supports DLLs, another possibility to get a toploop with findlib directives is to load the file "topfind" (normally installed in the standard library directory):

 $ ocaml
         Objective Caml version 3.04
 # #use "topfind";;
 Findlib has been successfully loaded. Additional directives:
   #require "package";;      to load a package
   #list;;                   to list the available packages
   #camlp4o;;                to load camlp4 (standard syntax)
   #camlp4r;;                to load camlp4 (revised syntax)
   Topfind.reset();;         to force that packages will be reloaded
 ~ : unit = ()
 # _

This works even in scripts (but the startup message is suppressed in this case).

The module is not thread-safe; if used in a multi-threaded script, all packgage loading must have happened before the first thread forks.

The Topfind module contains some functions simplifying package loading in scripts. Most important, there is a new directive #require for the same purpose (see below).

The Topfind module needs some initialization, in particular the predicates variable needs to be set, and the packages already compiled into the toploop needs to be declared by the don't_load function. If the toploop has been built by ocamlfind, the necessary initialization is automatically compiled in.

Directives

This module also defines the following directives for the toploop:

#require "<package>" loads the package (and if necessary the prerequisites of the package)
#camlp4o loads camlp4 and selects standard syntax
#camlp4r loads camlp4 and selects revised syntax
#list lists the available packages (calls external command "ocamlfind")
#thread enables multi-threading if possible
#predicates "p1,p2,..." adds these predicates

Functions and variables

val predicates : string list Pervasives.ref

The list of predicates used for package loading

val add_predicates : string list -> unit

Adds predicates to the list of predicates

val syntax : string -> unit

Emulates the -syntax option

val standard_syntax : unit -> unit

Adds predicates that select the standard syntax. Same as syntax "camlp4o"

val revised_syntax : unit -> unit

Adds predicates that select the revised syntax. Same as syntax "camlp4r"

val don't_load : string list -> unit

The packages named in pkglist are added to the list of packages which are already loaded.

val don't_load_deeply : string list -> unit

The packages named in pkglist and all direct and indirect ancestors are added to the list of packages which are already loaded.

val load : string list -> unit

The packages from the passed package list are loaded, from left to right, but packages that have already been loaded are left out.

val load_deeply : string list -> unit

The packages from the passed package list and all direct or indirect ancestors are loaded in topological order. Packages that have already been loaded are left out.

val reset : unit -> unit

All entries in the list of loaded packages that have been added by load or load_deeply functions are removed from this list. This means that if you execute the same load or load_deeply functions again, the packages will be reloaded.

val announce : unit -> unit

Output the startup message

val log : (string -> unit) Pervasives.ref

Function used to log messages from this module.

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