lib(fd_global_gac)


    This library is intended for global constraints for which GAC
    (generalized arc consistency, also called hyper arc consistency,
    or domain consistency) is maintained.  One example is a version
    of the alldifferent constraint which performs more pruning than
    the bound consistent version in the fd_global library.
    
    If a program uses multiple libraries, more than one version (with
    different degrees of propagation strength) of the declaratively
    same constraint may be visible.  In this case, the programmer has
    to explicitly state which version is wanted, either by using an
    import directive such as
    
        :- import alldifferent/1 from fd_global_gac.
    
    or by module-qualifying individual calls, such as
    
        ..., fd_global_gac:alldifferent(Xs), ...
    
    

