Proposal: Hot reload API

[znck]

The hot reload API offered by webpack, parcel et.el is similar, but there are minute differences which make it impossible to provide implementations for all bundlers out there. Hence, we should make hot API injectable.

What is required in hot reload?

• If <template> or <script> changes, reload/rerender the component.
• If <style module> changes, delete cached component constructor.
• If the component module is disposed of, do not inject <style>.

Proposed API:

{
  hot: {
    // 1. Wrap code with a conditional statement, checking if hot API is available or not.
    isHot: (expression: string) => string,
    // 2. Generate code calling `hot.accept` with passed handler function.
    accept: (fn: string) => string,
    // 3. Generate code calling `hot.dispose` with passed handler function.
    dispose: (fn: string) => string
  }
}

Related Issue: #51

[yyx990803]

Can you give an example of what webpack usage would look like with this API?

[yyx990803]

BTW, since most of the bundlers that support hot-reload in some way (webpack, parcel, browserify + hmr plugin) share somewhat similar API, we should probably have that as the default implementation, and use it when the hot is omitted (or disabled if hot is false). The API largely exists to make it configurable for the long term.