alt Hacker NewsYour comment makes me think of LabVIEW - if you're not familiar with it, it uses a visual programming language ("G") in which data flows down wires. The color of the wire indicates the wire's data type (blue for ints, orange for floats, green for bools, pink for strings) and the width of the wire indicates the dimensionality of the data (thin line = scalar, thick line = 1D array, double-thick = 2D array). The color is more than decorative or even assistive - it's essential to understanding the program.
I still wonder why every open-source visual programming language is either a toy for teaching or straight up awful, often not implementing but even loops, when LabVIEW has been doing it right for decades.
Despite its huge size and it installing several services that constantly run in the background, it's still one of my favorite "languages" of all time. It's the only one I've ever seen people going from never having programmed before to making simple but meaningful contributions in within a single day.