Function stackalloc::stackalloc_from_iter_exact

pub fn stackalloc_from_iter_exact<I, T, U, F>(iter: I, callback: F) -> U where
    F: FnOnce(&mut [T]) -> U,
    I: IntoIterator<Item = T>,
    I::IntoIter: ExactSizeIterator, 

Collect an exact size iterator into a stack allocated slice, call callback with this buffer, and then drop and deallocate the buffer.

See stackalloc_with_iter().

Size

If the implementation of ExactSizeIterator on I is incorrect and reports a longer length than the iterator actually produces, then the slice passed to callback is shortened to the number of elements actually produced.