// create new relation value from body as enumerable
public static RelValueST <Ttup> Create(IEnumerable <Ttup> tuples)
{
return(RelBaseST <Ttup> .Create <RelValueST <Ttup> >(new HashSet <Ttup>(tuples)));
}
// create new relation value from body as set
public static RelValueST <Ttup> Create(ISet <Ttup> tuples)
{
return(RelBaseST <Ttup> .Create <RelValueST <Ttup> >(tuples));
}