Multiple declarations error even with DuplicateRecordFields

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#1

I am using servant and persistent to define quite a lot of data types, while running stack build, I have error of Multiple declarations of a data type, I already have {-# LANGUAGE DuplicateRecordFields #-}, still getting this error. Search didn’t find more solution, any idea to resolve this?

My lts is 14.17, building on WSL Ubuntu 18.04

Thanks

#2

Hi @tdxiong, perhaps you could reduce your code to a smaller example and post that here, so we can help you out? It’s hard to tell what’s going wrong if we can’t see the code.

#3

My models are in seperate files for code organization. While thinking about how to put code here, seperate files came to my mind, I just added {-# LANGUAGE DuplicateRecordFields #-} to one file only after encountering this error, now I added it to all model files, no error then.

Thanks.

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