public boolean atom_length_2(Term arg0, Term len) throws PrologError { arg0 = arg0.getTerm(); if (arg0 instanceof Var) throw PrologError.instantiation_error(engine.getEngineManager(), 1); if (!arg0.isAtom()) throw PrologError.type_error(engine.getEngineManager(), 1, "atom", arg0); Struct atom = (Struct) arg0; return unify(len, new Int(atom.getName().length())); }