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Predicate call/1
Availability:built-in
Source[ISO]call(:Goal)
Call Goal. This predicate is normally used for goals that are not known at compile time. For example, the Prolog toplevel essentially performs read(Goal), call(Goal). Also a meta predicates such as ignore/1 are defined using call: 
ignore(Goal) :- call(Goal), !.
ignore(_).

Note that a plain variable as a body term acts as call/1 and the above is equivalent to the code below. SWI-Prolog produces the same code for these two progams and listing/1 prints the program above. 

ignore(Goal) :- Goal, !.
ignore(_).

Note that call/1 restricts the scope of the cut (!/0). A cut inside Goal only affects choice points created by Goal.

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LogicalCaptain said (2019-12-23T21:18:50):0 upvotes 0 0 downvotes
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Backtracking works as expected

?- call(member(X,[1,2,3])).
X = 1 ;
X = 2 ;
X = 3.

Doc changes

The text should probably be changed from

Note that clauses may have variables as subclauses, which is identical to call/1.

to

Note that clauses may have variables as goals. And such a variable X is identical to call(X).

See also

https://stackoverflow.com/questions/59437150/swi-prolog-description-of-call-1-clauses-may-have-variables-as-subclauses

There was a specific question on this at Discourse:

https://swi-prolog.discourse.group/t/i-dont-quite-understand-the-manual-text-for-call-1/