snaggen@programming.dev to Rust@programming.dev · 11 months agoDon't write Rust like it's Javajgayfer.comexternal-linkmessage-square33fedilinkarrow-up171arrow-down16
arrow-up165arrow-down1external-linkDon't write Rust like it's Javajgayfer.comsnaggen@programming.dev to Rust@programming.dev · 11 months agomessage-square33fedilink
minus-squaresleep_deprived@lemmy.worldlinkfedilinkarrow-up3·11 months agoBox is (basically) just the way to have memory on the heap. Here’s a direct comparison of how to do heap memory in C/++ and in rust: int* intOnHeap = (int*)malloc(sizeof(int)); *intOnHeap = 0; MyClass* classOnHeap = new MyClass(); let intOnHeap: Box = Box::new(0); let structOnHeap: Box = Box::new(MyStruct::default()); There can be a bit more to it with custom allocators etc. but that’s the only way most people will use boxes. So Box basically just means “a T is allocated somewhere and we need to free that memory when this value is dropped”.
Box
is (basically) just the way to have memory on the heap. Here’s a direct comparison of how to do heap memory in C/++ and in rust:int* intOnHeap = (int*)malloc(sizeof(int)); *intOnHeap = 0; MyClass* classOnHeap = new MyClass();
let intOnHeap: Box = Box::new(0); let structOnHeap: Box = Box::new(MyStruct::default());
There can be a bit more to it with custom allocators etc. but that’s the only way most people will use boxes. So
Box
basically just means “aT
is allocated somewhere and we need to free that memory when this value is dropped”.