Would replacing ' :: ' with ' . ' create ambiguities in C++?

Question

In C++, the operator :: is used to access classes, functions and variables in a namespace or class.

If the language specification used . instead of :: in those cases too like when accessing instance variables/methods of an object then would that cause possible ambiguities that aren't present with ::?

Given that C++ doesn't allow variable names that are also a type name, I can't think of a case where that could happen.

Clarification: I'm not asking why :: was chosen over ., just if it could have worked too?

Answer 1

Due to attempts to make C++ mostly compatible with the existing C code (which allows name collisions between object names and struct tags), C++ allows name collisions between class names and object names.

Which means that:

struct data {     static int member; };  struct data2 {     int member; };  void f(data2& data) {     data.member = data::member; } 

is legit code.

Answer 2

An example where both are valid, but refer to different objects:

#include <iostream>  struct A {     int i; };  struct B {     int i;     A B; };  int main() {     B x {0, 1};     std::cout << x.B.i << '\n';     std::cout << x.B::i << '\n'; } 

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