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The dispatch
function can be used to alias one function name to
another. It can be used to alias all calls to a particular function name
to another function, or the alias can be limited to only a particular
variable type. Consider the example
function y = spsin (x) printf ("Calling spsin\n"); fflush(stdout); y = spfun ("sin", x); endfunction dispatch ("sin", "spsin", "sparse matrix"); y0 = sin(eye(3)); y1 = sin(speye(3));
Which aliases the spsin
to sin
, but only for real sparse
matrices. Note that the builtin sin
already correctly treats
sparse matrices and so this example is only illustrative.
Replace the function f with a dispatch so that function r is called when f is called with the first argument of the named type. If the type is any then call r if no other type matches. The original function f is accessible using
builtin (
f, ...)
.If r is omitted, clear dispatch function associated with type.
If both r and type are omitted, list dispatch functions for f.
See also: builtin.
Call the base function f even if f is overloaded to some other function for the given type signature.
See also: dispatch.
A single dynamically linked file might define several functions. However, as Octave searches for functions based on the functions filename, Octave needs a manner in which to find each of the functions in the dynamically linked file. On operating systems that support symbolic links, it is possible to create a symbolic link to the original file for each of the functions which it contains.
However, there is at least one well known operating system that doesn't
support symbolic links. Making copies of the original file for each of
the functions is also possible, but is undesirable as it multiples the
amount of disk space used by Octave. Instead Octave supplies the
autoload
function, that permits the user to define in which
file a certain function will be found.
Define function to autoload from file.
The second argument, file, should be an absolute file name and should not depend on the Octave load path.
Normally, calls to
autoload
appear in PKG_ADD script files that are evaluated when a directory is added to the Octave's load path. To avoid having to hardcode directory names in file, it is customary to useautoload ("foo", fullfile (fileparts (mfilename ("fullpath")), "bar.oct"));Uses like
autoload ("foo", file_in_loadpath ("bar.oct"))are strongly discouraged.
With no arguments, return a structure containing the current autoload map.
See also: PKG_ADD.