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1-js/4-object-basics/03-object-methods/9-string-new-property/solution.md
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Try running it:
```js run
let str = "Hello";
str.test = 5; // (*)
alert(str.test);
```
There may be two kinds of result:
1. `undefined`
2. An error.
Why? Let's replay what's happening at line `(*)`:
1. When a property of `str` is accessed, a "wrapper object" is created.
2. The operation with the property is carried out on it. So, the object gets the `test` property.
3. The operation finishes and the "wrapper object" disappears.
So, on the last line, `str` has no trace of the property. A new wrapper object for every object operation on a string.
Some browsers though may decide to further limit the programmer and disallow to assign properties to primitives at all. That's why in practice we can also see errors at line `(*)`. It's a little bit farther from the specification though.
**This example clearly shows that primitives are not objects.**
They just can not store data.
All property/method operations are performed with the help of temporary objects.

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1-js/4-object-basics/03-object-methods/9-string-new-property/task.md
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importance: 5
---
# Can I add a string property?
Consider the following code:
```js
let str = "Hello";
str.test = 5;
alert(str.test);
```
How do you think, will it work? What will be shown?

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1-js/4-object-basics/03-object-methods/article.md
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@ -214,7 +214,6 @@ In this case `this` is `undefined` in strict mode. If we try to access `this.nam
In non-strict mode (if you forgot `use strict`) the value of `this` in such case will be the *global object* (`"window"` for browser, we'll study it later). This is just a historical thing that `"use strict"` fixes.
Please note that usually a call of a function using `this` without an object is not normal, but rather a programming mistake. If a function has `this`, then it is usually meant to be called in the context of an object.
```smart header="The consequences of unbound `this`"
@ -224,7 +223,6 @@ The idea of unbound, run-time evaluated `this` has both pluses and minuses. From
Here we are not to judge whether this language design decision is good or bad. We will understand how to work with it, how to get benefits and evade problems.
```
## Internals: Reference Type
An intricate method call can loose `this`, for instance: