public CharAtom() { this(new CharTopology()); }
public CharAtom(char a) { this(a,a); }
public CharAtom(char a, char b) { this(new CharTopology(a, b)); }
public CharAtom() { this(new CharTopology()); }
public CharAtom(char a) { this(a,a); }
public CharAtom(char a, char b) { this(new CharTopology(a, b)); }