[ ECLiPSe Predicate Database built-in.|Group Index| Full Index]

lib(+LibraryName)

Makes the library LibraryName available in the current module if not loaded already.

+LibraryName
String or atom.

Description

Used to load the library LibraryName into the system if it has not already been loaded. The currently used Prolog suffix(es) is appended to LibraryName and the resulting library is loaded if it exists.

The library will be loaded into the caller module unless there is an explicit :- module directive in the file.

The search path used when loading libraries is specified by the global flag library_path using the get_flag/2 and set_flag/2 predicates. This flag contains a list of strings containing the pathnames of the directories to be searched when loading a library file. User libraries may be added to the system simply by copying the desired file into the ECLiPSe library directory. Alternatively the library_path flag may be updated to point at a number of user specific directories.

lib(Lib) is similar to use_module(library(Lib)), however with lib/1 it is possible to load files that do not contain any module definitions or those with a different name than the file name. Another difference is that lib/1 uses ensure_loaded/1 to load the file and so it is recompiled if the file has been modified.

Fail Conditions

None.

Resatisfiable

No.

Exceptions

(4) Instantiation fault
LibraryName is not instantiated.
(5) Type error
LibraryName is neither a string nor an atom.
(173)
Library file LibraryName not found.

Examples


Success:
   [eclipse]: lib(sorts).
   loading the library /usr/local/ECLIPSE/lib/sorts.pl
   yes.
   [eclipse]: lib(sorts).
   yes.              % library already loaded - succeeds
Error:
   lib(X).            (Error 4).
   lib(1).            (Error 5).
   lib(no_lib).       (Error 173).

See Also

ensure_loaded / 1, lib / 2, get_flag / 2, set_flag / 2, use_module / 1