Hint
this is always the object immediately before the final dot — not a parent object.
const outer = {
name: 'outer',
inner: {
name: 'inner',
greet() { return this.name; },
},
};
console.log(outer.inner.greet());
const fn = outer.inner.greet;
console.log(fn?.call(outer));inner outer
Explanation: outer.inner.greet() — this is inner (the direct calling object). fn.call(outer) explicitly sets this to outer.
Key Insight: this is always the object immediately before the final dot — not a parent object.