src/main/java/com/basistech/tclre/Nfa.java
void copyins(State old, State newState) {
        Arc a;

        assert old != newState;

        for (a = old.ins; a != null; a = a.inchain) {
            cparc(a, a.from, newState);
        }
    }
void copyins(State old, State newState) {
        Arc a;

        assert old != newState;

        for (a = old.ins; a != null; a = a.inchain) {
            cparc(a, a.from, newState);
        }
    }
copyins - copy all in arcs of a state to another state