TypeScript Class Destructure

typescript-class-destructure.ts

interface GeoInterface {
  state: string;
  country: string;
}

interface PersonInterface {
  first: string;
  last: string;
  // a Person must contain a 'geo' object that matches 
  // the defined GeoInterface structure
  geo: GeoInterface;
}

export default class Person { 
  public first: string;
  public last: string;
  private geo: GeoInterface;


  // Enforce that the Class is being instantiated with a 
  // <PersonInterface> object, then destructure off the
  // props that we want to use for our Person instance and assign
  // them to the Classes props
  constructor({ first, last, geo }: PersonInterface) { 
    Object.assign(this, { first, last, geo });
  }

  // Adds .fullName property onto the <:Person> 
  // class instance
  public get fullName(): string {
    return `${this.first} ${this.last}`;
  }
  
  // Adds .location property onto the <:Person> 
  // class instance that returns a formatted location
  public get location(): string {
    const { state, country} = this.geo;
    return `${state}, ${country}`;
  }

  // Simple example method that uses the Classes internal state
  // to return info about the Person instance
  whoAmI(): string {
    const { fullName, location } = this;
    return `My name is ${fullName}, and I'm from ${location}`;
  }
}