Explain the code using ASCII art

Note from the translator: typically a Friday article on Tuesday morning ... why not?



Most people are visuals. They use images to get to the bottom of the problem. But mainstream programming languages, on the contrary, are based on textual representation. The resulting gap between text and graphics is filled with ASCII images drawn using text characters and inserted into the program source code. I love them! Once I threw a cry on Twitter and they sent me much more examples than I expected. Thanks to everyone involved. This topic came up with some excellent examples that I collected and put into categories. For each image, a link to the corresponding repository is given.

Data structures

One of the most common uses of ASCII art in code is to illustrate the data structure.

The first example from LLVM source code:


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Location of fields in the data structure in Jikes RVM:


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Tree rotation in Musl:


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Two-way queue in Rust:


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Swift compiler internals:


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Location of elements in the Malloc header:


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State machines

Javascript Profiling: RPC


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in Cloud Spanner:


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I / O Stream State:


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Domain Logic

Control flow in the decompiled NWScript program:


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ECC internals:


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Number formatting:


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Quantum loop:


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Balancing memory management tasks in the kernel of the operating system:


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Type compatibility (this is a particularly impressive case, because ASCII art is code here!)


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Format DBF file:


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Lookup-table for image processing:


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Color function form:


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URL structure:


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"Short" help on canceling operations in emacs:


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Translator's note: there are still a lot of similar charts on the link

Geometry

Height control in the on-board computer Apollo (!!!):


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Splitting the image into segments:


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Boomerang paths in Nethack:


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Drawing the borders of the element in CSS:


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Quadrant tree:


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Control the speed of the machine:


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Scrolling web pages:


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I hope did you like it!

Additional example from translator:

Graph of interpolation of value:


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