Function acquire

src/lib.rs:267–284

TODO: Relax the TrustedLen constraint, opting instead to allocate the larger bound, and release any extra unused space after running the iterator.

(i: I)

// TODO: Relax the TrustedLen constraint, opting instead to allocate the larger bound,
// and release any extra unused space after running the iterator.
pub fn acquire<T, I: Iterator<Item=T> + TrustedLen>(i: I) -> StackAlloc<T> {
	THREAD_LOCAL_POOL.with(|rc| {
		let len = i.size_hint();
		assert_eq!(Some(len.0), len.1); // Runtime check for ExactSizedIterator, since this isn't working for some obvious cases like repeat(v).take(5)
		let pool = rc.borrow_mut().acquire(len.0);
		let mut p = pool.ptr;
		// TODO: To adhere to the standards of the nomicon, this needs to handle drop correctly in
		// the face of a panic. Probably the thing to do is to have acquire just return a pointer tuple, and then
		// wrap it up in the drop structure at the end.
		for item in i {
			unsafe {
				ptr::write(p, item);
				p = p.add(1);
			}
		}
		pool
	})
}

#[cfg(test)]
mod tests {