code review

Package.swift

@@ -1,4 +1,29 @@
-// swift-tools-version:5.4
+//
+//  Package.swift
+//  FSPagerView
+//
+//  Created by Wenchao Ding on 22/02/2017.
+//  Copyright © 2017 Wenchao Ding. All rights reserved.
+//
+//  Permission is hereby granted, free of charge, to any person obtaining a copy
+//  of this software and associated documentation files (the "Software"), to deal
+//  in the Software without restriction, including without limitation the rights
+//  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//  copies of the Software, and to permit persons to whom the Software is
+//  furnished to do so, subject to the following conditions:
+//
+//  The above copyright notice and this permission notice shall be included in
+//  all copies or substantial portions of the Software.
+//
+//  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+//  THE SOFTWARE.
+
+
 import PackageDescription
 
 let package = Package(

Sources/FSPagerView.swift

@@ -512,7 +512,8 @@ open class FSPagerView: UIView,UICollectionViewDataSource,UICollectionViewDelega
     @objc(scrollToItemAtIndex:animated:)
     open func scrollToItem(at index: Int, animated: Bool) {
         guard index < self.numberOfItems else {
-            fatalError("index \(index) is out of range [0...\(self.numberOfItems-1)]")
+            assertionFailure("index \(index) is out of range [0...\(self.numberOfItems-1)]")
+			return
         }
         let indexPath = { () -> IndexPath in
             if let indexPath = self.possibleTargetingIndexPath, indexPath.item == index {