Currying article

without-compose.js

// Data example
const items = [{name: 'Bruce' }, {name: 'Fabs'}, {name: 'Bruce'}, {name: 'Gaby'}];

/**
 * @description Filter by one where condition
 * @param w Where condition function
 * @returns {Function} filter function
 */
const filter = w => a => a.filter(w);

/**
 * @description Create a where condition function
 * @param k Criteria key name
 * @param v Criteria value
 * @returns {Function} Where condition function
 */
const where = (k, v) => i => i[k] === v;

/**
 * @description Create a map function
 * @param fnMap Function to set on map callback
 * @returns {Function} Map function
 */
const map = fnMap => f => f.map(fnMap);

/**
 * @description Create a modification function
 * @param k Key to set any value
 * @param v Value to set
 * @returns {Function} Modification function
 */
const applier = (k, v) => x => x[k] = v;

// Apply the modification
map(applier('lastname', 'Wayne'))(filter(where('name', 'Bruce'))(items));