en.javascript.info/1-js/04-object-basics/04-object-methods/3-why-this/solution.md
Ilya Kantor 9ad9063d00 up
2016-11-28 21:35:42 +03:00

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Here's the explanations.
1. That's a regular object method call.
2. The same, brackets do not change the order of operations here, the dot is first anyway.
3. Here we have a more complex call `(expression).method()`. The call works as if it were split into two lines:
```js no-beautify
f = obj.go; // calculate the expression
f(); // call what we have
```
Here `f()` is executed as a function, without `this`.
4. The similar thing as `(3)`, to the left of the dot `.` we have an expression.
To explain the behavior of `(3)` and `(4)` we need to recall that property accessors (dot or square brackets) return a value of the Reference Type.
Any operation on it except a method call (like assignment `=` or `||`) turns it into an ordinary value, which does not carry the information allowing to set `this`.