Why I want to introduce namespace

case1__with_namespace.ts

class SomeDevice {
  constructor(private peripheral: Noble.Peripheral) {
  }

  public connect(): void {
    this.peripheral.connect();
  }

  public disconnect(): void {
    this.peripheral.disconnect();
  }
}

case2__without_namespace_1.ts

import { Peripheral } from "@types/noble";

class SomeDevice {
  constructor(private peripheral: Peripheral) {
  }

  public connect(): void {
    this.peripheral.connect();
  }

  public disconnect(): void {
    this.peripheral.disconnect();
  }
}

case3__without_namespace_2.ts

import * as noble from "noble";

class SomeDevice {
  constructor(private peripheral: noble.Peripheral) {
  }

  public connect(): void {
    this.peripheral.connect();
  }

  public disconnect(): void {
    this.peripheral.disconnect();
  }
}

These are simple implementation of Peripheral wrapper class.
Currently only case2 and case3 work.
After introducing namespace, all of case1, case2 and case3 work.

case1
After introducing namespace, we can write like this.
Any imports are not needed because tsc automatically load @types/noble.

case2
Currently this kind of import statement is needed despite tsc automatically load @types/noble.

case3
We can also write like this, but noble implementation is not needed in this class.