| ▲ | WD-42 a day ago |
| 0 allocations after the program initializes. |
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| ▲ | tialaramex a day ago | parent | next [-] |
| RAII doesn't imply allocating. My guess is that you're assuming all user defined types, and maybe even all non-trivial built-in types too, are boxed, meaning they're allocated on the heap when we create them. That's not the case in C++ (the language in question here) and it's rarely the case in other modern languages because it has terrible performance qualities. |
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| ▲ | Gupie a day ago | parent | prev | next [-] |
| Open a file in the constructor, close it in the destructor. RAII with 0 allocations. |
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| ▲ | dh2022 a day ago | parent [-] | | std::vector<int> allocated and freed on the stack will allocate an array for its int’s on the heap… | | |
| ▲ | Gupie 10 hours ago | parent | next [-] | | Sure, but my point was that RAII doesn't need to involve the heap. Another example would be acquiring abd releasing a mutex. | |
| ▲ | usefulcat 19 hours ago | parent | prev [-] | | I've heard that MSVC does (did?) that, but if so that's an MSVC problem. gcc and clang don't do that. https://godbolt.org/z/nasoWeq5M | | |
| ▲ | menaerus 17 hours ago | parent [-] | | WDYM? Vector is an abstraction over dynamically sized arrays so sure it does use heap to store its elements. | | |
| ▲ | aw1621107 7 hours ago | parent [-] | | I think usefulcat interpreted "std::vector<int> allocated and freed on the stack" as creating a default std::vector<int> and then destroying it without pushing elements to it. That's what their godbolt link shows, at least, though to be fair MSVC seems to match the described GCC/Clang behavior these days. |
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| ▲ | nicoburns a day ago | parent | prev | next [-] |
| RAII doesn't necessarily require allocation? |
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| ▲ | jjmarr a day ago | parent | prev [-] |
| Stack "allocations" are basically free. |
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