Multi tool use

Xcode/Swift 'filename used twice' build error

I'm new to Swift and am struggling with an error after I have (possibly) correctly installed a 3rd party framework via CocoaPods.

The error is as follows.

<unknown>:0: error: filename "MainController.swift" used twice: '/Users/myname/Desktop/ProjectName/ProjectName/Controllers/MainController.swift' and '/Users/myname/Desktop/ProjectName/ProjectName/Controllers/MainController.swift'
<unknown>:0: note: filenames are used to distinguish private declarations with the same name
Command /Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/swiftc failed with exit code 1


As far as I can gather from other forums and seemingly obvious is that I have to remove one of the files being used twice. However I can't see where they would be installed twice. If I remove the file from the /Controllers folder the error becomes 'file not found' etc.

So my question is, where would these conflicting files be located and how do I safely remove one of them? Or is it more that there is only one file but it is being used twice - in which case how do I stop that?

Many thanks.

Ok I feel that comments are getting lost so am clarifying here to see if can trigger an answer as not been able to build and run this since yesterday.

I now have only the swift files in the Pods->Pods/MainController folder.

When I build I get a file not found. However the file it is looking for is in App->Controllers folder which is where I deleted it from. If I put the file in there I get the 'used twice' error.

So how do I stop it trying to find the file in the Controllers and look for it in the Pods?

Thanks

7 Answers
7

Try to search, if you have added same ViewController - MainController.swift twice.

MainController.swift

If not, then search class MainController in codebase.

class MainController

Regarding Pods, it is preferred to use all Pods as frameworks,

So try using 'use_frameworks!' in your Podfile, and then from terminal reinstall the pods "pod install".

'use_frameworks!'

Podfile

pod install

Check the file is not included twice in the target's "Build Phases" "Compile Sources" settings.
It can happen when you merge project.pbxproj.

If this is core data related and you are not having Xcode generate the entities for you at build time (you created them manually yourself), and you are experiencing this issue, chances are that you didn't check update the entity in the .xcdatamodelld file. What happens is that Xcode will create a duplicate class of your existing class, since you told Xcode to generate the entity at runtime.


In the Data Model Inspector change "Module" to "Current Product Module", and "Codegen" to "Manual/None".

The main idea is... yes, check for duplicated classes. But in my case I had none. I had a big project, added WatchKit, lots of stuff and at some point I had a "duplicated" class. I removed the duplicate but the problem remained. To fix it I did this:

This can be in your project.pbxproj when you make merge with github or similar tool.

This can be fix opening the project.pbxproj in your favorite text editor and removing the duplicates declarations.

Hope that fix your problem.

I came across this issue by remove the used twice file from Compile Sources as below image. Selected the file, and click the -. Then clean and build.

I would add on to Josh O'Conners answer in that making the changes he recommended was the root of my problem. I did have to clean the build folder by hitting shift-option-command-k to complete the fix.

By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.