Why does C have a distinction between -> and .?

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I don’t think there’s anything crazy about what you’ve said. Using . for pointers to structs would work.

However, I like the fact that pointers to structs and structs are treated differently.

It gives some context about operations and clues as to what might be expensive.

Consider this snippet, imagine that it’s in the middle of a reasonably large function.

s.c = 99;
f(s);

assert(s.c == 99);

Currently I can tell that s is a struct. I know that it’s going to be copied in its entirety for the call to f. I also know that that assert can’t fire.

If using . with pointers to struct were allowed, I wouldn’t know any of that and the assert might fire, f might set s.c (err s->c) to something else.

The other downside is that it would reduce compatibility with C++. C++ allows -> to be overloaded by classes so that classes can be ‘like’ pointers. It’s important that . and -> behave differently. “New” C code that used . with pointers to structs would no probably not be acceptable as C++ code any more.

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