Benneth Yankey papayankey
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| function countBy<T extends { [key: string]: any }, K extends keyof T>( | |
| collection: T[], | |
| key: K | |
| ) { | |
| return Object.values(collection).reduce( | |
| (accum: { [key: string]: any }, curr) => { | |
| accum[curr[key]] = | |
| accum[curr[key]] !== undefined ? (accum[curr[key]] += 1) : 1; | |
| return accum; | |
| }, |
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| function groupBy<T extends { [key: string]: any }, K extends keyof T>( | |
| collection: T[], | |
| key: K | |
| ) { | |
| return Object.values(collection).reduce( | |
| (accum: { [key: string]: any }, curr) => { | |
| accum[curr[key]] = | |
| accum[curr[key]] !== undefined ? [...accum[curr[key]], curr] : [curr]; | |
| return accum; | |
| }, |
papayankey
/ object-filter.js
Created
March 15, 2020 11:02
object property filter or picker with support for nested objects
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| let toString = Object.prototype.toString; | |
| // strict object check | |
| function isObject(value) { | |
| return toString.call(value) === '[object Object]'; | |
| } | |
| // strict array check | |
| function isArray(value) { | |
| return toString.call(value) === '[object Array]'; |