code: function prod( arr, clbk ) {
  	var len = arr.length,
  		p = 1,
  		v,
  		i;
  	for ( i = 0; i < len; i++ ) {
  		v = clbk( arr[ i ], i );
  		if ( v === 0 ) {
  			return 0;
  		}
  		p *= v;
  	}
  	return p;
  }
docs: FUNCTION: prod( arr, clbk )
  Computes an array product using an accessor.
  
  @param {Array} arr - input array
  @param {Function} accessor - accessor function for accessing array values
  @returns {Number} product