RxHotModule
When in the presence of Hot Module Replacement, export an Observable.
Example
// hot.js module 'hello world'
// entry.js if typeof hotsubscribe === 'function' // Module is hot hot else console
If HMR is disabled, rxHot
returns the data object by default. To change
this behavior and always return an Observable, pass the {alwaysRx: true}
to rxHot
// hot.js module alwaysRx: true 'hello world'
// entry.js // Module is always Observablehot