8ee50178f3
Correct: `Array.from()` (it’s a static method) Incorrect: `Array.join()` (doesn’t exist; it’s a prototype method) This patch uses the common `#` syntax to denote `.prototype.`.
23 lines
669 B
Markdown
23 lines
669 B
Markdown
### deepClone
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Creates a deep clone of an object.
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Use recursion.
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Use `Object.assign()` and an empty object (`{}`) to create a shallow clone of the original.
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Use `Object.keys()` and `Array.prototype.forEach()` to determine which key-value pairs need to be deep cloned.
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```js
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const deepClone = obj => {
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let clone = Object.assign({}, obj);
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Object.keys(clone).forEach(
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key => (clone[key] = typeof obj[key] === 'object' ? deepClone(obj[key]) : obj[key])
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);
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return Array.isArray(obj) ? (clone.length = obj.length) && Array.from(clone) : clone;
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};
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```
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```js
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const a = { foo: 'bar', obj: { a: 1, b: 2 } };
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const b = deepClone(a); // a !== b, a.obj !== b.obj
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```
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