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Update deepMapKeys

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Resolves #1139
This commit is contained in:
Angelos Chalaris
2020-04-20 11:05:56 +03:00
parent 2176ab6e9a
commit 977dc31cfb
1 changed files with 7 additions and 6 deletions
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13
snippets/deepMapKeys.md
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@ -6,18 +6,19 @@ tags: object,recursion,advanced
Deep maps an object's keys. Deep maps an object's keys.
Creates an object with the same values as the provided object and keys generated by running the provided function for each key. Creates an object with the same values as the provided object and keys generated by running the provided function for each key.
Use `Object.keys(obj)` to iterate over the object's keys. Use `Object.keys(obj)` to iterate over the object's keys.
Use `Array.prototype.reduce()` to create a new object with the same values and mapped keys using `fn`. Use `Array.prototype.reduce()` to create a new object with the same values and mapped keys using `fn`.
```js ```js
const deepMapKeys = (obj, f) => const deepMapKeys = (obj, fn) =>
Array.isArray(obj) Array.isArray(obj)
? obj.map(val => deepMapKeys(val, f)) ? obj.map(val => deepMapKeys(val, fn))
: typeof obj === 'object' : typeof obj === 'object'
? Object.keys(obj).reduce((acc, current) => { ? Object.keys(obj).reduce((acc, current) => {
const key = fn(current);
const val = obj[current]; const val = obj[current];
acc[f(current)] = acc[key] =
val !== null && typeof val === 'object' ? deepMapKeys(val, f) : (acc[f(current)] = val); val !== null && typeof val === 'object' ? deepMapKeys(val, fn) : val;
return acc; return acc;
}, {}) }, {})
: obj; : obj;
@ -51,4 +52,4 @@ const upperKeysObj = deepMapKeys(obj, key => key.toUpperCase());
} }
} }
*/ */
``` ```