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minor fixes

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Ilya Kantor 2021-07-22 23:37:04 +03:00
parent df215cd566
commit 614c85ad5d
1 changed files with 5 additions and 6 deletions
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1-js/07-object-properties/01-property-descriptors/article.md
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@ -221,12 +221,6 @@ Math.PI = 3; // Error
Making a property non-configurable is a one-way road. We cannot change it back with `defineProperty`. Making a property non-configurable is a one-way road. We cannot change it back with `defineProperty`.
To be precise, non-configurability imposes several restrictions on `defineProperty`:
1. Can't change `configurable` flag.
2. Can't change `enumerable` flag.
3. Can't change `writable: false` to `true` (the other way round works).
4. Can't change `get/set` for an accessor property (but can assign them if absent).
**The idea of "configurable: false" is to prevent changes of property flags and its deletion, while allowing to change its value.** **The idea of "configurable: false" is to prevent changes of property flags and its deletion, while allowing to change its value.**
Here `user.name` is non-configurable, but we can still change it (as it's writable): Here `user.name` is non-configurable, but we can still change it (as it's writable):
@ -263,6 +257,11 @@ delete user.name;
Object.defineProperty(user, "name", { value: "Pete" }); Object.defineProperty(user, "name", { value: "Pete" });
``` ```
```smart header="The only attribute change possible: writable true -> false"
There's a minor exception, that we have to mention.
We can change `writable: true` to `false` for a non-configurable property, thus making the property readonly (can add another layer of protection). But not the other way around.
```
## Object.defineProperties ## Object.defineProperties