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Reason
type schoolPerson =
  | Teacher
  | Director
  | Student(string);

let greeting = person =>
  switch (person) {
  | Teacher => "Hey Professor!"
  | Director => "Hello Director."
  | Student("Richard") =>
    "Still here Ricky?"
  | Student(anyOtherName) =>
    "Hey, " ++ anyOtherName ++ "."
  };

type schoolPerson = Teacher | Director | Student(string);

let greeting = person =>
  switch (person) {
  | Teacher => "Hey Professor!"
  | Director => "Hello Director."
  | Student("Richard") => "Still here Ricky?"
  | Student(anyOtherName) => "Hey, " ++ anyOtherName ++ "."
  };
Reason lets you write simple, fast and quality type safe code while leveraging both the JavaScript & OCaml ecosystems.
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Types without hassle

Powerful, safe type inference means you rarely have to annotate types, but everything gets checked for you.

Easy JavaScript interop

Use packages from NPM/Yarn with minimum hassle, or even drop in a snippet of raw JavaScript while you're learning!

Flexible & Fun

Make websites, animations, games, servers, cli tools, and more! Take a look at these examples to get inspired.

QuickStart

npm install -g bs-platform
bsb -init my-first-app -theme basic-reason
cd my-first-app
npm run start

It runs in watch mode, so any changes to files will be picked up and compiled. Read more here!

Examples

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