uses some swift amazing feature, provides a very short and clear way to make constraints in code.
3.2 updated to swift5.
current latest version is 3.2.
you must know what 'left.attr = right.attr * m + c' means for AutoLayout.
import XAutoLayout
// use `=/`` to make composite equal witch creates an array of NSLayoutConstraint
// TODO: add sample codeThe API is not friendly for developers. Too long and too complicated. wish XAutoLayout will make our lives easier.