gistfile1.txt

// don't make functions within a loop
model.get('things').then(things => {
  things.forEach(thing => {
    thing.get('attachment').then(attachment => {
      thing.set('foo', true);
      attachment.set('bar', true);
    });
  })
});

// attempted solution
model.get('things').then(things => {
  things.forEach(thing => {
    // how do I pass attachment without making a function?
    thing.get('attachment').then(attachmentFunction(thing));
  })
});

var attachmentFunction = function(attachment, thing) {
  thing.set('foo', true);
  attachment.set('bar', true);
};