DeclareCategory("IsRack", IsAttributeStoringRep);
DeclareCategory"IsRackElm", IsMultiplicativeElement);

DeclareRepresentation( "IsRackElmRep", IsPositionalObjectRep, [ 1 ]);
DeclareOperation("RackElmConstructor", [IsRack, IsInt]);

BindGlobal("RackElmFamily", NewFamily("RackElmFamily", IsRackElm));
BindGlobal("RackElmType", NewType(RackElmFamily, IsRackElm));
BindGlobal("RackType", NewType(CollectionsFamily( RackElmFamily [1,,3, 4 ,6,7,8, 9,10,11, 16, 21, 22 ,27, 28, 41,43, 45 ,

### To create/recognize racks 
DeclareOperation("Rack", [IsList]);
DeclareAttribute("Rack2YB", IsRack);
DeclareAttribute("AsList", IsRack);
DeclareAttribute("Enumerator", IsRack);

DeclareAttribute("Permutations", IsRack);
DeclareAttribute("MatrixOfRack", IsRack);