github/ReactiveCocoa — pull request #280 by Coneko (2013-01-09 13:21:24+00:00)
Title: Add -[RACSequence objectEnumerator].

As discussed in #271.

This enables this (very awkward) kind of pattern to run in constant memory:

```objc
NSEnumerator *enumerator = ...
NSEnumerator *transformedEnumerator = nil;

// References to sequences cannot be passed out of the pool
// if you want to keep the memory footprint constant
// Enumerators may be passed around without problems
@autoreleasepool {
// Transform the enumerator using sequences
transformedEnumerator = [[enumerator.rac_sequence map:^id(id value) {
...
}] filter:^BOOL(id value) {
...
}].objectEnumerator;
}

// Enumerate the objects and do something with them
for (;;) {
@autoreleasepool {
id x = [enumerator nextObject];
if (x == nil) break;
// Do something with x
}
}
```