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Bound Instance Methods
Bound Instance Methods
When a function is assigned to a class instance property, that function is bound to the instance.
Before ES2016, you might bind functions to class instances in the constructor, e.g. this.func = this.func.bind(this). Binding here ensures that a class's instance function is invoked with the correct context.
With ES2016 class instance properties, we can instead write func = () =>. func is then bound to the class instance at construction.