4 ms·

Nothing about lambdas requires heap allocation. See also: C++, Rust

• porridgeraisin 1y ago
  If the lambda captures some value, and also outlives the current scope, then that captured value has to necessarily be heap allocated.
  • do_not_redeem 1y ago
    That would be a bug, so just... don't do that? If you return a pointer to a local variable that outlives the scope, the pointer would be dangling. Does that mean we should ban pointers? If you close over a pointer to a local variable that outlives the scope, the closure would be dangling. Does that mean we should ban closures?
  • noselasd 1y ago
    No, (in C++) the lambda can capture the the variable by value, and the lambda itself can be passed around by value. If you capture a variable by reference or pointer that your lambda outlives, your code got a serious bug.
    • gf000 1y ago
      And in Rust, it will enforce correct usage via the borrow checker - the outlive case simply will not compile. If you do want it, you have the option to, say, heap allocate.