group

Categorize elements from an array into distinct groups

Usage

Given an array of items, group will build up an object where each key is an array of the items that belong in that group.

import * as 
import _
_ from 'radashi'

const 
const fish: {
    name: string;
    source: string;
}[]
fish = [
  {
    
name: string
name: 'Marlin',
    
source: string
source: 'ocean',
  },
  {
    
name: string
name: 'Bass',
    
source: string
source: 'lake',
  },
  {
    
name: string
name: 'Trout',
    
source: string
source: 'lake',
  },
]

const 
const fishBySource: {
    [x: string]: {
        name: string;
        source: string;
    }[] | undefined;
}
fishBySource = 
import _
_.
function group<{
    name: string;
    source: string;
}, string>(array: readonly {
    name: string;
    source: string;
}[], getGroupId: (item: {
    name: string;
    source: string;
}, index: number) => string): {
    [x: string]: {
        name: string;
        source: string;
    }[] | undefined;
}
Categorizes elements from an array into distinct groups. The
function returns an object where each key is a category identifier
determined by the getGroupId function, and each value is an array
containing all elements that belong to that category.
@see ― https://radashi.js.org/reference/array/group
@example 
group([1, 2, 3, 4], (n) => n % 2 === 0 ? 'even' : 'odd')
// { even: [2, 4], odd: [1, 3] }
@version ― 12.1.0
group(
const fish: {
    name: string;
    source: string;
}[]
fish, 
f: {
    name: string;
    source: string;
}
f => 
f: {
    name: string;
    source: string;
}
f.
source: string
source) // => { ocean: [marlin], lake: [bass, trout] }