What am I doing wrong here with my errorHandler?

[johanalkstal]

I'm trying to learn Giraffe and am hitting a roadblock setting up a basic app.

I have this errorHandler,

let errorHandler (ex : Exception) (logger : ILogger) =
    logger.LogError($"An unhandled exception has occurred while executing the request. {ex.Message}")
    clearResponse >=> ServerErrors.INTERNAL_ERROR ex.Message

And at app.UseGiraffeErrorHandler(errorHandler) I'm getting the following error, The type 'exn' is not compatible with the type 'Exception'

From what I can gather from reading the docs and the source code comments, exn is supposed to be a System.Exception but the compiler seems to disagree, and I'm at my wits end on what the issue is?

Any help is much appreciated!

[johanalkstal]

The answer is to change to this,

let errorHandler (ex : exn) (logger : ILogger)

exn is an abbreviation for the CLI type System.Exception.

I don't know why it wasn't possible to just use System.Exception directly but I'm sure there's a good reason for that.