type NonImp<L, R> = And<L, Not<R>>;
Material non-implication
This type alias takes Boolean parameters and evaluates to
either True or False.
assert_eq!(NonImp::<True ,True >::VALUE,false);
assert_eq!(NonImp::<False,True >::VALUE,false);
assert_eq!(NonImp::<True ,False>::VALUE,true );
assert_eq!(NonImp::<False,False>::VALUE,false);