Convert an array of objects to a single object

JavaScript version
const toObject = (arr, key) => arr.reduce((a, b) => ({ ...a, [b[key]]: b }), {});
// Or
const toObject = (arr, key) => Object.fromEntries(arr.map((it) => [it[key], it]));
TypeScript version
const toObject = <T extends Record<string, any>, K extends keyof T>(arr: T[], key: K): Record<string, T> => (
arr.reduce((a, b) => ({ ...a, [b[key]]: b }), {})
);
const toObject = <T extends Record<string, any>, K extends keyof T>(arr: T[], key: K): Record<string, T> => (
Object.fromEntries(arr.map((it) => [it[key], it]))
);
Example
toObject(
[
{ id: '1', name: 'Alpha', gender: 'Male' },
{ id: '2', name: 'Bravo', gender: 'Male' },
{ id: '3', name: 'Charlie', gender: 'Female' },
],
'id'
);
/*
{
'1': { id: '1', name: 'Alpha', gender: 'Male' },
'2': { id: '2', name: 'Bravo', gender: 'Male' },
'3': { id: '3', name: 'Charlie', gender: 'Female' },
}
*/