The coroutining object provides a portable abstraction over how common coroutining predicates are made available by the supported backend Prolog systems (ECLiPSe, LVM, 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 link in a web browser.


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

| ?- logtalk_load(coroutining(loader)).


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

| ?- logtalk_load(coroutining(tester)).


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