Exemple #1
0
    Object* const_missing(STATE, Symbol* sym, CallFrame* call_frame) {
      Module* under;
      StaticScope* scope = call_frame->static_scope();
      if(scope->nil_p()) {
        under = G(object);
      } else {
        under = scope->module();
      }

      Array* args = Array::create(state, 1);
      args->set(state, 0, sym);
      return under->send(state, call_frame, G(sym_const_missing), args);
    }
Exemple #2
0
    Object* const_get(STATE, CallFrame* call_frame, Symbol* name, bool* found) {
      StaticScope *cur;
      Object* result;

      *found = false;

      call_frame = call_frame->top_ruby_frame();

      // Ok, this has to be explained or it will be considered black magic.
      // The scope chain always ends with an entry at the top that contains
      // a parent of nil, and a module of Object. This entry is put in
      // regardless of lexical scoping, it's the default scope.
      //
      // When looking up a constant, we don't want to consider the default
      // scope (ie, Object) initially because we need to lookup up
      // the superclass chain first, because falling back on the default.
      //
      // The rub comes from the fact that if a user explicitly opens up
      // Object in their code, we DO consider it. Like:
      //
      // class Idiot
      //   A = 2
      // end
      //
      // class ::Object
      //   A = 1
      //   class Stupid < Idiot
      //     def foo
      //       p A
      //     end
      //   end
      // end
      //
      // In this code, when A is looked up, Object must be considering during
      // the scope walk, NOT during the superclass walk.
      //
      // So, in this case, foo would print "1", not "2".
      //
      cur = call_frame->static_scope();
      while(!cur->nil_p()) {
        // Detect the toplevel scope (the default) and get outta dodge.
        if(cur->top_level_p(state)) break;

        result = cur->module()->get_const(state, name, found);
        if(*found) return result;

        cur = cur->parent();
      }

      // Now look up the superclass chain.
      cur = call_frame->static_scope();
      if(!cur->nil_p()) {
        Module* mod = cur->module();
        while(!mod->nil_p()) {
          result = mod->get_const(state, name, found);
          if(*found) return result;

          mod = mod->superclass();
        }
      }

      // Lastly, check Object specifically
      result = G(object)->get_const(state, name, found, true);
      if(*found) return result;

      return Qnil;
    }