package
static if(Leafs.length == 1)
static if(!(is(Leafs[0] == Leaf!(Ridx, idx, T), string Ridx, string idx, T) || isBasicType!(Leafs[0])))
static if(!(is(Leafs[0] == Func!(Ridx, func, Leafs_), string Ridx, alias func, Leafs_...)))
static if(is(Leafs[0] == Tree!(Ridx, L, R, OP, Leafs_), string Ridx, L, R, string OP, Leafs_...))