counting

Creates an object with counts of occurrences of items

Usage

Given an array of objects and an identity callback function to determine how each object should be identified. Returns an object where the keys are the id values the callback returned and each value is an integer telling how many times that id occurred.

import * as 
import _
_ from 'radashi'

const 
const gods: {
    name: string;
    culture: string;
}[]
gods = [
  {
    
name: string
name: 'Ra',
    
culture: string
culture: 'egypt',
  },
  {
    
name: string
name: 'Zeus',
    
culture: string
culture: 'greek',
  },
  {
    
name: string
name: 'Loki',
    
culture: string
culture: 'greek',
  },
]

const 
const countingByCulture: Partial<Record<string, number>>
countingByCulture = 
import _
_.
function counting<{
    name: string;
    culture: string;
}, string>(array: readonly {
    name: string;
    culture: string;
}[], identity: (item: {
    name: string;
    culture: string;
}) => string): Partial<Record<string, number>>
Counts the occurrences of each unique value returned by the
identity function when applied to each item in the array.
If no occurrences are found, the key will not be present in the
returned object.
@see ― https://radashi.js.org/reference/array/counting
@example 
counting([1, 2, 3, 4], (n) => n % 2 === 0 ? 'even' : 'odd')
// { even: 2, odd: 2 }
@version ― 12.1.0
counting(
const gods: {
    name: string;
    culture: string;
}[]
gods, 
g: {
    name: string;
    culture: string;
}
g => 
g: {
    name: string;
    culture: string;
}
g.
culture: string
culture) // => { egypt: 1, greek: 2 }