Anyone who is interested in pattern matching and the visitor pattern (and the benefits of various encodings of state and behavior) who hasn't seen them should c

Anyone who is interested in pattern matching and the visitor pattern (and the benefits of various encodings of state and behavior) who hasn't seen them should check out: * Li Haoyi's Zero-Overhead Tree Processing with the Visitor Pattern (https://www.lihaoyi.com/post/ZeroOverheadTreeProcessingwiththeVisitorPattern.html https://www.lihaoyi.com/post/ZeroOverheadTreeProcessingwitht...) * Noel Welsh's Uniting Church and State: FP and OO Together (https://noelwelsh.com/posts/uniting-church-and-state/ https://noelwelsh.com/posts/uniting-church-and-state/ or https://www.youtube.com/watch?v=IO5MD62dQbI https://www.youtube.com/watch?v=IO5MD62dQbI is you like video) * Bruno C. d. S. Oliveira and William R. Cook's Extensibility for the Masses Practical Extensibility with Object Algebras (https://www.cs.utexas.edu/~wcook/Drafts/2012/ecoop2012.pdf https://www.cs.utexas.edu/~wcook/Drafts/2012/ecoop2012.pdf)