How do I make an NSView move to the front of all NSViews

Here’s another way to accomplish this that’s a bit more clear and succinct:

[viewToBeMadeForemost removeFromSuperview];
[self addSubview:viewToBeMadeForemost positioned:NSWindowAbove relativeTo:nil];

Per the documentation for this method, when you use relativeTo:nil the view is added above (or below, with NSWindowBelow) all of its siblings.