calls a grammar rule with the inputsymbols of a list.

phrase(+Term, +List)

phrase/2 calls a grammar rule Term with the inputsymbols listed in List.

Arguments

Term                   term
List                   list of symbols

Examples

polish(Stack, Result) --> 
     [X], {integer(X)}, polish([X|Stack], Result).
polish([Y,X|Stack], Result) --> 
     [(+)], {Z is X+Y}, polish([Z|Stack], Result).
polish([Y,X|Stack], Result) --> 
     [(-)], {Z is X-Y}, polish([Z|Stack], Result).
polish([Z], Z) --> 
     [].

main(X) :-
     phrase(polish([], Result), [2,3,(+),1,(-)]),
     println(['result = ', Result]).

Succeeds and prints "result = 4".

Standard

This predicate is not part of the ISO-Prolog Standard.

See also

expand_term/2.

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