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by MontyCarloHall 300 days ago
Both languages let you use explicit `this` but don’t mandate it. The “static closure” approach is great. I don’t like having to explicitly pass `this` as a parameter to every method call as in the OP (or worse, the confusing Python approach of forcing `self` to be explicitly written in every non-static method signature but having it be implicitly passed during method calls).

What I don’t like is being able to reference instance members without `this`, e.g.

   void foo() {
      int x = bar + 1; // should be illegal: it can be hard to distinguish if `bar` is a local variable versus an instance member
      int y = this->bar + 1; // disambiguation is good
   }
1 comments

> int x = bar + 1; // should be illegal: it can be hard to distinguish if `bar` is a local variable versus an instance member

If it was this->bar it could be a member, it could also be a static variable. A bar on its own could be local or it could be in any of the enclosing scopes or namespaces. Forcing "this" to be explicit doesn't make the code any clearer on its own.

The guy was referring to the explicit case where bar is a member variable. The cases where it is in the local scope under scoping rules or the global scope are not really an issue, since you can check the function definition to find if it is local. In the case that it is not in the function definition, then it is in the global scope in C. If implicit this were not done in C++, that would also be the case in C++, provided you do the sane thing and use the std namespace for everything. Just thinking about the headaches namespaces could cause when looking for such definitions with cscope gives me yet another reason to stay away from C++ whenever possible.