34 lines
		
	
	
		
			906 B
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			34 lines
		
	
	
		
			906 B
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
import baseIteratee from './_baseIteratee.js';
 | 
						|
import baseSum from './_baseSum.js';
 | 
						|
 | 
						|
/**
 | 
						|
 * This method is like `_.sum` except that it accepts `iteratee` which is
 | 
						|
 * invoked for each element in `array` to generate the value to be summed.
 | 
						|
 * The iteratee is invoked with one argument: (value).
 | 
						|
 *
 | 
						|
 * @static
 | 
						|
 * @memberOf _
 | 
						|
 * @since 4.0.0
 | 
						|
 * @category Math
 | 
						|
 * @param {Array} array The array to iterate over.
 | 
						|
 * @param {Function} [iteratee=_.identity] The iteratee invoked per element.
 | 
						|
 * @returns {number} Returns the sum.
 | 
						|
 * @example
 | 
						|
 *
 | 
						|
 * var objects = [{ 'n': 4 }, { 'n': 2 }, { 'n': 8 }, { 'n': 6 }];
 | 
						|
 *
 | 
						|
 * _.sumBy(objects, function(o) { return o.n; });
 | 
						|
 * // => 20
 | 
						|
 *
 | 
						|
 * // The `_.property` iteratee shorthand.
 | 
						|
 * _.sumBy(objects, 'n');
 | 
						|
 * // => 20
 | 
						|
 */
 | 
						|
function sumBy(array, iteratee) {
 | 
						|
  return (array && array.length)
 | 
						|
    ? baseSum(array, baseIteratee(iteratee, 2))
 | 
						|
    : 0;
 | 
						|
}
 | 
						|
 | 
						|
export default sumBy;
 |