I've been fascinated by constraints ever since I did some work on iOS, using UIKit. The layout constraint mechanism was super cool. I've been trying to build a

I've been fascinated by constraints ever since I did some work on iOS, using UIKit. The layout constraint mechanism was super cool. I've been trying to build a programming language for UI designers, and one of the goals is to let designers describe layouts using constraint-based code that reads as close to natural language as possible. Something like: // "the blue box is directly beneath the red box" BlueBox { top: @RedBox.bottom } // "the red box is 10 pixels to the right of the blue box RedBox { left: @BlueBox.right + 10 }