reason-loadable

Summary

🔥 Suspense/Lazy for ReasonReact.

• Installation
• Support
• Examples
• Non-ReasonReact component)
• API
• Special thanks to

Installation

npm install reason-loadable --save

Then add "reason-loadable" in "bsconfig.json" :

"bs-dependencies": [
 "reason-loadable"
]

You can now use "ReLoadable" module.

Note : "ReLoadable" contain type definition, it doesn't add any single bit into your project.

Support

• ReasonReact component (JSX v3). ✔️
• Non-ReasonReact component (third-party React component or your own plain JavaScript React component). ✔️

ReasonReact JSX v2 isn't supported : Please consider migrating to JSX v3 (new ReasonReact hook components).

Examples

1. Create a ReasonReact hook component (JSX v3).

/* HelloWorld.re */
[@react.component]
let make = (~name) => <h1> (React.string("Hello world " ++ name)) </h1>;
 
/* Export default is necessary because React lazy function always resolve the default export. */
let default = make;

1. Create type-safe lazy component with "ReLoadable.lazy_" and "ReLoadable.import".

/* LazyHelloWorld.re */
module type T = (module type of WithPure);
 
/*
  Needed for BuckleScript to not import the original component :
  See https://github.com/BuckleScript/bucklescript/issues/3543
*/
let unsafePlaceholder: module T = [%raw {|{}|}];
 
module UnsafePlaceholder = (val unsafePlaceholder);
 
let makeProps = UnsafePlaceholder.makeProps;
 
let make =
  ReLoadable.lazy_(() => ReLoadable.import(UnsafePlaceholder.make, "./HelloWord.bs.js"));

1. Render lazy component anywhere in your ReasonReact app with "React.Suspense".

/* App.re */
[@react.component]
let make = () => {
  <React.Suspense fallback={<div> (React.string("Loading ...")) </div>}>
    <LazyHelloWorld name="Zeus" />
  </React.Suspense>;
};

More example are available in repository.

Non-ReasonReact component

1. Create type-safe lazy component with "ReLoadable.lazy_" and "ReLoadable.import".

/* LazyButton.re */
/* You have to type non-ReasonReact component props explicitly. */
module type T = {
  [@react.component]
  let make: (~text: string) => React.element;
};
 
/*
  Needed for BuckleScript to not import the original component :
  See https://github.com/BuckleScript/bucklescript/issues/3543
*/
let unsafePlaceholder: module T = [%raw {|{}|}];
 
module UnsafePlaceholder = (val unsafePlaceholder);
 
let makeProps = UnsafePlaceholder.makeProps;
 
/* "@my-component-lib/button" should have a default export. */
let make =
  ReLoadable.lazy_(() => ReLoadable.import(UnsafePlaceholder.make, "@my-component-lib/button"));

1. Render lazy component anywhere in your ReasonReact app with "React.Suspense".

/* App.re */
[@react.component]
let make = () => {
  <React.Suspense fallback={<div> (React.string("Loading ...")) </div>}>
    <LazyButton text="Click !" />
  </React.Suspense>;
};

API

ReLoadable.import: (Js.t('a) => React.element), string) => Js.Promise.t(Js.t('a) => React.element)

Dynamic import React component.

ReLoadable.lazy_: (unit => Js.Promise.t('a)) => 'a

React.lazy binding.

Special thanks to

• @jchavarri

• @rickyvetter

• @bloodyowl

• @cristianoc

• @thangngoc89

• @jchavarri (https://github.com/jchavarri/reason-react-lazy-loading)