.. _library_coroutining:

``coroutining``
===============

The ``coroutining`` object provides a portable abstraction over how
common coroutining predicates are made available by the supported
backend Prolog systems (ECLiPSe, XVM, SICStus Prolog, SWI-Prolog,
Trealla Prolog, and YAP) that provide them. Partial support for XSB is
provided (the predicate ``frozen/2`` is not available and calls to it
fail).

Calls to the library predicates are inlined when compiled with the
``optimize`` flag turned on. In this case, there is no overhead compared
with calling the abstracted predicates directly.

See also the ``dif`` library.

API documentation
-----------------

Open the
`../../docs/library_index.html#coroutining <../../docs/library_index.html#coroutining>`__
link in a web browser.

Loading
-------

To load all entities in this library, load the ``loader.lgt`` file:

::

   | ?- logtalk_load(coroutining(loader)).

Testing
-------

To test this library predicates, load the ``tester.lgt`` file:

::

   | ?- logtalk_load(coroutining(tester)).

Usage
-----

Load this library from your application loader file. To call the
coroutining predicates using implicit message sending, add the following
directive to any object or category calling the predicates (adjust the
list to the predicates actually called):

::

   :- uses(coroutining, [
       dif/2, dif/1, freeze/2, frozen/2, when/2
   ]).
