Not line-art to ASCII art, so not exactly what you're looking for, but PlantUML [1] generates software-related diagrams from ASCII text. There's a plug-in for J

Not line-art to ASCII art, so not exactly what you're looking for, but PlantUML [1] generates software-related diagrams from ASCII text. There's a plug-in for JetBrains IDEs such as PyCharm that will render the diagram in a pane in the IDE: you can include the ASCII text in a comment in code. You can also generate documentation (I use Sphinx, for Python stuff) that includes diagrams generated from code. [1] http://plantuml.com/ http://plantuml.com/