type inference

For the final episode of Elixir Wizards’ Season 11 “Branching Out from Elixir,” we’re featuring a recent discussion from the Software Unscripted podcast. In this conversation, José Valim, creator of Elixir, interviews Richard Feldman, creator of Roc. They compare notes on the process and considerations for creating a language. This episode covers the origins of creating a language, its influences, and how goals shape the tradeoffs in programming language design. José and Richard share anecdotes from their experiences guiding the evolution of Elixir and Roc. The discussion provides an insightful look at the experimentation and learning involved in crafting new languages. Topics discussed in this episode What inspires the creation of a new programming language Goals and use cases for a programming language Influences from Elm, Rust, Haskell, Go, OCaml, and more Tradeoffs involved in expressiveness of type systems Opportunistic mutation for performance gains in a functional language Minimum version selection for dependency resolution Build time considerations with type checking and monomorphization Design experiments and rolling back features that don’t work out History from the first simple interpreter to today's real programming language Design considerations around package management and versioning Participation in Advent of Code to gain new users and feedback Providing performance optimization tools to users in the future Tradeoffs involved in picking integer types and arithmetic Comparing floats and equality checks on dictionaries Using abilities to customize equality for custom types Ensuring availability of multiple package versions for incremental upgrades Treating major version bumps as separate artifacts Roc's focus on single-threaded performance Links mentioned in this episode Software Unscripted Podcast https://feeds.resonaterecordings.com/software-unscripted Roc Programming Language https://www.roc-lang.org/ Roc Lang on Github https://github.com/roc-lang/roc Elm Programming Language https://elm-lang.org/ Elm in Action by Richard Feldman https://www.manning.com/books/elm-in-action Richard Feldman on Github https://github.com/rtfeldman Lua Programming Language https://www.lua.org/ Vimscript Guide https://google.github.io/styleguide/vimscriptfull.xml OCaml Programming Language https://ocaml.org/ Advent of Code https://adventofcode.com/ Roc Language on Twitter https://twitter.com/roclang Richard Feldman on Twitter https://twitter.com/rtfeldman Roc Zulip Chat https://roc.zulipchat.com Clojure Programming Language https://clojure.org/ Talk: Persistent Data Structures and Managed References by Rich Hickey https://www.youtube.com/watch?v=toD45DtVCFM Koka Programming Language https://koka-lang.github.io/koka/doc/index.html Flix Programming Language https://flix.dev/ Clojure Transients https://clojure.org/reference/transients Haskell Software Transactional Memory https://wiki.haskell.org/Softwaretransactional_memory Rust Traits https://doc.rust-lang.org/book/ch10-02-traits.html CoffeeScript https://coffeescript.org/ Cargo Package Management https://doc.rust-lang.org/book/ch01-03-hello-cargo.html Versioning in Golang https://research.swtch.com/vgo-principles Special Guests: José Valim and Richard Feldman.

It’s the Season 10 finale of the Elixir Wizards podcast! José Valim, Guillaume Duboc, and Giuseppe Castagna join Wizards Owen Bickford and Dan Ivovich to dive into the prospect of types in the Elixir programming language! They break down their research on set-theoretical typing and highlight their goal of creating a type system that supports as many Elixir idioms as possible while balancing simplicity and pragmatism. José, Guillaume, and Giuseppe talk about what initially sparked this project, the challenges in bringing types to Elixir, and the benefits that the Elixir community can expect from this exciting work. Guillaume's formalization and Giuseppe's "cutting-edge research" balance José's pragmatism and "Guardian of Orthodoxy" role. Decades of theory meet the needs of a living language, with open challenges like multi-process typing ahead. They come together with a shared joy of problem-solving that will accelerate Elixir's continued growth. Key Topics Discussed in this Episode: Adding type safety to Elixir through set theoretical typing How the team chose a type system that supports as many Elixir idioms as possible Balancing simplicity and pragmatism in type system design Addressing challenges like typing maps, pattern matching, and guards The tradeoffs between Dialyzer and making types part of the core language Advantages of typing for catching bugs, documentation, and tooling The differences between typing in the Gleam programming language vs. Elixir The possibility of type inference in a set-theoretic type system The history and development of set-theoretic types over 20 years Gradual typing techniques for integrating typed and untyped code How José and Giuseppe initially connected through research papers Using types as a form of "mechanized documentation" The risks and tradeoffs of choosing syntax Cheers to another decade of Elixir! A big thanks to this season’s guests and all the listeners! Links and Resources Mentioned in this Episode: Bringing Types to Elixir | Guillaume Duboc & Giuseppe Castagna | ElixirConf EU 2023 (https://youtu.be/gJJH7a2J9O8) Keynote: Celebrating the 10 Years of Elixir | José Valim | ElixirConf EU 2022 (https://youtu.be/Jf5Hsa1KOc8) OCaml industrial-strength functional programming https://ocaml.org/ ℂDuce: a language for transformation of XML documents http://www.cduce.org/ Ballerina coding language https://ballerina.io/ Luau coding language https://luau-lang.org/ Gleam type language https://gleam.run/ "The Design Principles of the Elixir Type System" (https://www.irif.fr/_media/users/gduboc/elixir-types.pdf) by G. Castagna, G. Duboc, and J. Valim "A Gradual Type System for Elixir" (https://dlnext.acm.org/doi/abs/10.1145/3427081.3427084) by M. Cassola, A. Talagorria, A. Pardo, and M. Viera "Programming with union, intersection, and negation types" (https://www.irif.fr/~gc/papers/set-theoretic-types-2022.pdf), by Giuseppe Castagna "Covariance and Contravariance: a fresh look at an old issue (a primer in advanced type systems for learning functional programmers)" (https://www.irif.fr/~gc/papers/covcon-again.pdf) by Giuseppe Castagna "A reckless introduction to Hindley-Milner type inference" (https://www.lesswrong.com/posts/vTS8K4NBSi9iyCrPo/a-reckless-introduction-to-hindley-milner-type-inference) Special Guests: Giuseppe Castagna, Guillaume Duboc, and José Valim.