code: function ( array, from, to ) {
  
  		if ( AnimationUtils.isTypedArray( array ) ) {
  
  			// in ios9 array.subarray(from, undefined) will return empty array
  			// but array.subarray(from) or array.subarray(from, len) is correct
  			return new array.constructor( array.subarray( from, to !== undefined ? to : array.length ) );
  
  		}
  
  		return array.slice( from, to );
  
  	}
docs: same as Array.prototype.slice, but also works on typed arrays