Why does C need the scope resolution operator

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Why is the:: operator used in C++ instead of the. operator for this purpose? 

There is no distinct operator in Java, and it works great. 

Is there a distinction between C++ and Java that necessitates the use of a separate operator in order for C++ to be parsable?

My only idea is that:: is required for precedence reasons, but I'm not sure why it should take precedence over, say,... 

The only way I can see it happening is if something like

a.b::c;

would be parsed as

a.(b::c);

, but I can't think of a situation where this syntax would be lawful in any case.

Maybe "they do different things, so they might as well look different" is the case. 

That, however, does not explain why : : has higher priority than.

Jun 1, 2022 in C++ by Nicholas
• 7,760 points
652 views

1 answer to this question.

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No. There is no scope resolution operator in C.

One can be found in C++ (::).

Perhaps you (or your book) are mixing up C and C++.

You inquired how to get to the global variable a from a function (here main) having its own local variable a.

This isn't possible in C.

It's lexically incorrect.

Of course, you could take the variable's address from somewhere else and use it as a pointer, but that's a different story.

Simply rename the variable to something like 'don't do that.'
answered Jun 1, 2022 by Damon
• 4,960 points

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