ReasonML vs TypeScript

Question

What are the tradeoffs between ReasonML (https://reasonml.github.io/) and TypeScript (https://www.typescriptlang.org/)?

Answer 1

There are lot of languages nowadays that target JavaScript. Choosing one of them depends on your needs and the idioms you're comfortable with.

JavaScript has a dynamic type system. Some developers prefer a static one.

• TypeScript or Haxe solves this with a new language that is statically typed and only transpiles to JavaScript.

• Flow is a JavaScript preprocessor that targets the same issue but without the need to learn a new language. I prefer this approach if you only need a type system.

Some JS developers want more and use more functional programming idioms (algebraic data structures, immutability, pattern matching, ...). A lot of programming languages can do it (OCaml, Haskell, ReasonML, F#, Scala, ...).

• ReasonML is a syntax for OCaml that can compile to either native or JavaScript through BuckleScript. All you can achieve with Reason can also be achieved with OCaml, except that the ReasonML syntax accepts JSX. ReasonML can easily target node.js app, react.js app or native app.

TypeScript is easy to learn if you come from the Java or C# world.

ReasonML is harder to learn if you never developed with an ML language (OCaml or F#)

My advice:

• If you just need a static type system, you should consider TypeScript

• If you need a type system to do a react.js or react-native app, you should consider ReasonML because ReasonReact is a huge improvement over react.js

• If you need a functional programming language that compiles to js, you should consider ReasonML