zlacker

The company I worked for in the early 80’s was in the market for a CAD system, and they all had constraint systems in the UI, and showed them in the demos.

>>cardif+(OP)
CAD people got this a long time ago, but, unfortunately, HTML people never did. Layout is a 2D constraint problem, but HTML/CSS approaches it as a procedural problem, partly because early browsers were so compute and bandwidth constrained.