问题
After upgrading Xcode to 7.3, I just found that some modules are stricken out while importing, like in this screenshot:
But after adding the module (so just pressing enter) everything is fine. What does that mean? The module here is written in Swift and works fine.
回答1:
This is a bug. We have fixed it in 218010af, which should be included in the Swift 2.2.1 release and is included in the 2016-04-12-a developer snapshot.
回答2:
The strikethrough occurs if you try to import a module that has already been imported by your file or module:
In this case, I have already imported Foundation (which implicitly imports CoreFoundation), so Xcode is telling you that there is no need to import either module again.
回答3:
I changed the order of the imports
import Foundation
import UIKit
import LayerKit
import Atlas < red line
import Foundation
import UIKit
import Atlas
import LayerKit
Some notes that may be causing it:
LayerKit importing Atlas even though LayerKit is the lower level API Atlas is the UI layer
Both were Cocoapod imports
Error appeared when I created an 2nd Schema for App Store/Enteprise releases and cleaned one and switch to the other.
- Deleting Derived Data didnt clear it.
- So tried rearranging them and red line disappeared
回答4:
It usually happens when a framework is already imported by any other framework you have already been imported.
For example, UIKit is already imported with Foundation so you don't need to import it manually.
来源：https://stackoverflow.com/questions/35671637/the-module-required-to-be-imported-but-displayed-in-strikethrough-font-in-xcode