ensure_loaded/1ensure_loaded(+Files)
Load the specified Prolog source and/or QOF file(s) into memory, if not already loaded and up to date.
.pl or .qof
extension may be omitted in a file specification.
Loads each of the specified files except for files that have previously been loaded and that have not been changed since they were last loaded.
In the case of non-module-files, a file is not considered to have been
previously loaded if it was loaded into a different module. For
restrictions on non-module QOF-files, and how they can be loaded, see
load_files/[1,2]. In this case the file is loaded again and a warning
message is printed to let you know that two copies of the file have
been loaded (into two different modules). If you want two copies
of the file, you can avoid the warning message by changing the
ensure_loaded/1 command to a compile/1 command. If you do
not want multiple copies of the file, make the file a module-file.
When ensure_loaded/1 is called from an embedded command in a file being
compiled by qpc, each specified file is compiled from source into QOF unless
there is already a QOF file that is more recent than the source.
When ensure_loaded/1 is called in a runtime system, all predicates will be
loaded as dynamic predicates and therefore this code will run slower. The reason for this is that the compiler is not
available in runtime systems.
This predicate is defined as:
ensure_loaded(Files) :-
load_files(Files, [if(changed),
load_type(latest)]).
For further details on loading files, see ref-lod.
instantiation_error
type_error
existence_error
fileerrors flag is off, the
predicate fails instead of raising this exception.
permission_error
fileerrors flag is off, the
predicate fails instead of raising this exception.
compile/1, load_files/[1,2].