text: 
  let counts = {
    company: 1,
    building: 1
  };
  
  export let BUILDINGS = [];
  export let COMPANIES = [];
  
  function building(name) {
    let b = { name, id: counts.building++, companyId: this.company.id };
    BUILDINGS.push(b);
    this.company.buildings.push(b.id);
  }
  
  function company(name, cb) {
    let c = { name, buildings: [], id: counts.company++ };
    COMPANIES.push(c);
    let ctxt = {
      company: c
    };
    ctxt.building = building.bind(ctxt);
    cb.apply(ctxt);
  }
  
  company('Yahoo', function() {
    this.building(`Yahoo - Building A`);
    this.building(`Yahoo - Building B`);
    this.building(`Yahoo - Building C`);
    this.building(`Yahoo - Building D`);
  });
  
  company('Flurry', function() {
    this.building(`Flurry HQ`);
  });
  
  company('Tumblr', function() {
    this.building(`Tumblr HQ`);
  });