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lib(+LibraryName)

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

Description

This is a shorthand: lib(Lib) is identical to use_module(library(Lib)).

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 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.

Modes and Determinism

Modules

This predicate is sensitive to its module context (tool predicate, see @/2).

Exceptions

(4) instantiation fault
LibraryName is not instantiated.
(5) type error
LibraryName is neither a string nor an atom.
(80) not a module
Library file does not contain a matching module.
(173) library not found
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, existing_file / 4, get_flag / 2, set_flag / 2, use_module / 1