You need to store the captured data somewhere if the lambda is called after the outer function returns. AFAIK C++ (or rather std::function) will heap-allocate if the capture size goes above some arbitrary limit (similar to small-string optimizations in std::string). Not sure how Rust handles this case, probably through some "I can't let you do that, Dave" restrictions ;)
alt Hacker News
You need to store the captured data somewhere if the lambda is called after the outer function returns. AFAIK C++ (or rather std::function) will heap-allocate if the capture size goes above some arbitrary limit (similar to small-string optimizations in std::string). Not sure how Rust handles this case, probably through some "I can't let you do that, Dave" restrictions ;)