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# indomain(?Var)

Instantiate Var to a value in its domain.

?Var
  An integer or a domain variable

## Description

This predicate instantiates the domain variable Var to a value from its domain. Its starts with the smallest element in the domain and on backtracking successive elements are taken. It is used mostly to find an instantiation of the variable which is consistent with the current set of constraints in labeling procedures. If List is a list of all domain variables occurring in the program, the simplest labeling procedure is written as

            labeling([]).
            labeling([Var|Rest]) :-
                indomain(Var),
                labeling(Rest).

### Fail Conditions

None.

### Resatisfiable

Yes.

## See Also

:: / 2, #:: / 2, par_indomain / 1, labeling / 1, fd_search : search / 6