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bs-generators v0.2.0

BuckleScript bindings to JavaScripts Generator objects



Author: Matthew Scharley
Contributors: See contributors on GitHub
Bugs/Support: Github Issues
Copyright: 2018
License: MIT license
Status: Active


This package provides bindings to use and create JavaScripts' Generator objects, aka function*() {}.

Using this library you can consume JavaScript libraries that use function* and you can create objects that operate like that JS syntax to send into JavaScript land as well.

A word of warning. This library should only really be considered for interoperation with existing JavaScript code that uses Generators. I do not recommend using these types on their own inside ReasonML/Ocaml codebases.


Depending on your package manager of choice,

npm install bs-generators


yarn add bs-generators


The best API documentation so far is the interface file.

Using a function* defined in JavaScript and provided to your Reason code

open JsGenerator;

/* Create a generator - pretend this comes from the outside */
let jsGen: JsGenerator.fnU(int) = [%raw "function *() { yield 1; yield 2; yield 3 }"];
let gen = jsGen();

/* Iterate over the generator and stop when doneGet returns true */
Js.log("Running the JavaScript generator:");
let i = ref(gen->next());
while (! (i^)->doneGet) {
  i := gen->next();

Creating a Generator to pass into JavaScript code

let reGen: JsGenerator.fn(int) = _ => JsGenerator.fromNext({
  /* Create a mutable counter */
  let i = ref(0);
  () => {
    if (i^ < 3) {
      i := i^ + 1;
      /* You can also return Some(None) to send an undefined value to JS without closing the Generator */
    else {
      /* Close the Generator */

Js.log("Running the Reason generator:");
[%%raw "for (var x of reGen()) { console.log(x); }"];


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