The instanceof mechanism cross package/module versions.
npm install graceful-instanceof
The instanceof mechanism cross package versions.
``js
export default class MyClass {
constructor (options) {
if (this instanceof MyClass) {
return options
}
// do something with options
}
}
`
We intend to do something like this:
`js
const instance = new MyClass(options)
instance === new MyClass(instance) // true
`
But what happens if the instance is came from another version of the module?
`
abc.js
node_modules
|-- foo # version 1.0.0
|-- index.js # which export default MyClass
|-- bar
|-- node_modules # version 1.1.0
| |-- foo
| |-- index.js # also exports MyClass
|-- index.js # which exports default the instance of MyClass
And in abc.js
`js
import bar from 'bar'
import MyClass from 'foo'
bar === new MyClass(bar) // FALSE!!
// Something BOOOOOOOOOOM !!!
`
`sh`
$ npm install graceful-instanceof
`js
import instanceOf from 'graceful-instanceof'
const type = instanceOf('foo:MyClass')
class MyClass {
constructor (options) {
if (type.is(options)) {
return options
}
type.attach(this)
}
}
const instace = new MyClass(options)
instance === new MyClass(instance) // true
``
And it also works cross versions.
MIT