People tend to be visual: we use pictures to understand problems. Mainstream programming languages, on the other hand, operate in an almost completely different kind of abstract space, leaving a big gap between programs and pictures. This piece is about pictures drawn using a text character set and then embedded in source code. I love these! The other day I asked around on Twitter for more examples and the responses far exceeded expectations (thanks everyone!). There are a ton of great examples in the thread; here I’ve categorized a few of them. Click on images go to the repositories.
One of the most common kinds of ASCII art in code is illustrating the shape of a data structure.
The example I started with comes from LLVM:
The layout of a data structure in the Jikes RVM:
A tree rotate in Musl:
Double-ended queue from the Rust library:
Swift compiler internals:
Malloc header layout:
JavaScript profiling:
RPCs in Cloud Spanner:
