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45 lines
1.1 KiB
Markdown
45 lines
1.1 KiB
Markdown
# Freeze An Object, Sorta
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You can freeze a JavaScript object using `Object.freeze` which will help
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enforce some immutability practices. Don't be fooled though, you can still
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modify arrays and objects in the frozen object.
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Here is what the docs have to say:
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> The Object.freeze() method freezes an object: that is, prevents new
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> properties from being added to it; prevents existing properties from being
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> removed; and prevents existing properties, or their enumerability,
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> configurability, or writability, from being changed, it also prevents the
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> prototype from being changed.
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And here is `Object.freeze` in action:
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```javascript
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> const things = {one: "two", hello: "world", cats: ["Von Neumann", "Sosa"]}
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undefined
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> Object.freeze(things)
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{one: "two", hello: "world", cats: Array(2)}
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> things.one = "three"
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"three"
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> things.dogs = []
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[]
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> delete things.hello
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false
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> things
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{one: "two", hello: "world", cats: Array(2)}
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> things.cats.push("Sneaky")
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3
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> things
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{one: "two", hello: "world", cats: Array(3)}
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```
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See the [MDN
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Docs](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Object/freeze)
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for more details.
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h/t Jake Worth
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