Screwing around with visual constraints using swift operators. I think I've read about others writing this, but was just curious how it looked/worked. Needs a lot of cleanup before anyone ever uses it.
Lets you do things like: Align a view horizontally to both edges of its superview:
|-label-|
Align a view vertically to both edges of its superview:
^-label-^
Align label 10 px from the leading edge of its superview, then a 20 pixel gap, then view2, aligned to the trailing edges of its superview:
|-20-label-10-label2-20-|
Align label2 vertically to be have its top 20 pixels below label's, and its bottom 20 pixels above label:
label.topAnchor-20-label2-20-label.bottomAnchor
Vertically, align view to have a height greater-than-or-equal-to 50 at a low priority, and a 50 pixel gap to the bottom of the screen (again, low priority),
^-view/<=150~250-50~250-^