
memberchk(+Term, ?List)

   Succeeds if Term is a member of the list List.



Arguments
   +Term               Prolog term.
   ?List               List or a variable.

Type
   library(lists)

Description
   Unifies Term with the first matching element of the list List.

   If List is not instantiated, memberchk/2 binds List to a new partial
   list containing an element Term.

   The definition of this Prolog library predicate is:

memberchk(X,[X|_]) :- !.
memberchk(X,[_|T]):- memberchk(X,T).

   This predicate does not perform any type testing functions.
	

Modes and Determinism
   memberchk(+, +) is semidet
   memberchk(+, -) is det

Fail Conditions
      Fails if Term is not a member of the list List.



Resatisfiable
      No.

Examples
   
Success:
      memberchk(0,[1,B,2]). (gives B=0).
      memberchk(1,[1,X]).   (gives X=_g76).
      memberchk(1,X), memberchk(2,X).
                            (gives X=[1,2|_g98]).

Fail:
      memberchk(0,[1,2,3,4]).





See Also
   member / 2
