{flow} provides tools to visualize as flow diagrams the logic of functions, expressions or scripts and ease debugging.

Use cases are :

  • Deciphering other people’s code
  • Getting more comfortable with our own code by easing a visual understanding of its structure
  • Documentation
  • Debugging
  • Inspect unit test results
  • Providing a higher level view of an algorithm to collaborators
  • Education


Install from CRAN with:

Or install development version from github:



Using default nomnoml engine


Using plantuml engine (make sure the {plantuml} package is installed).

flow_view(rle, engine = "plantuml")



Make sure to check the vignettes for a detailed breakdown of all features.

{flow} is built on top of Javier Luraschi’s {nomnoml} package, and Rainer M Krug ’s {plantuml} package, the latter only available from github at the moment.