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:- object(switch,
	imports(assumptions)).

	:- info([
		version is 1:1:0,
		author is 'Orginal example by Paul Tarau et al. Adapted to Logtalk by Paulo Moura.',
		date is 2016-05-18,
		comment is 'Example of defining a switch...case control construct using linear assumptions.'
	]).

	:- public(test/1).
	:- mode(test(+integer), one).
	:- info(test/1, [
		comment is 'Test predicate for the switch control construct.',
		argnames is ['Value']
	]).

	:- meta_predicate(switch(*, 0)).
	switch(Selector, Body) :-
		^^assumel(case(Selector)),
		call(Body).

	default :-
		case(_).

	test(X) :-
		switch(X, (
			case(1) -> write(one) ;
			case(2) -> write(two) ;
			default -> write(unexpected(X))
		)), nl.

	:- private(case/1).
	:- dynamic(case/1).

:- end_object.
