When to use 'ioError. userError 'instead of' error '

Question

When reading the source code of the package network, I noticed that it is widely used ioError (userError ("Error description"))to raise errors during I / O operations.

Since this is not the first time I have seen this, I was wondering what the difference is in the practice of using this template instead of from . errorPrelude

I know what ioError . userErrorcalls in the monad , but calls a anywhere, but in the end both are destined to interrupt the program, showing a simple error message. IOExceptionIOerror ErrorCall

In which scenarios ioError . userErrorwould it be beneficial to use error?

Answer 1

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