this post was submitted on 03 May 2024
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HOLY SHIT!! IS THAT A MOTHERF*CKING C++ REFERENCE???

int& a = b;

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[–] [email protected] 5 points 6 months ago (1 children)

never mind, I looked it up. It’s a “reference” instead of a pointer. Similar, but unlike a pointer it doesn’t create a distinct variable in memory of its own.

I'm almost sure it does create a distinct variable in memory. Internally it's still a pointer, specifically a const pointer (not to be confused with a pointer to a const value; it's the address that does not change). Think about it as a pointer that is only ever dereferenced and never used as a pointer. So yes, like the other commenter said, like an alias.

[–] [email protected] 3 points 6 months ago (2 children)

I don't think references are variables: you can't modify them, and AFAIR you can't have pointers to them, with the possible but unlikely exception of non-static member references.

[–] [email protected] 6 points 6 months ago

An int& reference is just as much of a variable as int* const would be (a const pointer to a non-const int). "Variable" might be a misnomer here, but it takes just as much memory as any other pointer.

[–] [email protected] 4 points 6 months ago

For references within a scope, you’re probably right. For references that cross scope boundaries (i.e. function parameters), they necessarily must consume memory (or a register). Passing a parameter to a function call consumes memory or a register by definition. If a function call is inlined, that means its instructions are copy-pasted to the call location so there’s no actual call in the compiled code.