How do you set up a HandleResult > for any T?

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How do you set up a HandleResult<Result<T>> for any T?

See original GitHub issue

I understand the requirements of having a strongly-typed HandleResult<T> and only having one T per policy, however I’m looking to do something with a library that returns a generic wrapped result, with the error message contained within the wrapper.

Example (from memory code, may contain issues):

interface IWebCallResult<T> {
     public bool Success { get; }
     public Error? Error { get; }  // Will be filled in if there's an error.
     public T? Data { get; } // Will be filled in if there's no error
}

I’d like to do something like:

TimoutPolicy = Policy
    .HandleResult<IWebCallResult>(r => r.Success == false && (r.Error?.Message.Contains("timed out") ?? false))
    .RetryAsync();

In other words, if the success is false and the error is timed out, then retry, otherwise fail. I have about 40 of these, so writing loads of boilerplate all saying exactly the same really feels DRY. Is there a way to handle this in Polly?

As it stands, I’ve got to do something like:

StringTimeoutPolicy = Policy
    .HandleResult<IWebCallResult<string>>(r => r.Success == false && (r.Error?.Message.Contains("timed out") ?? false))
    .RetryAsync();
ObjectTimeoutPolicy = Policy
    .HandleResult<IWebCallResult<object>>(r => r.Success == false && (r.Error?.Message.Contains("timed out") ?? false))
    .RetryAsync();
ThingTimeoutPolicy = Policy
    .HandleResult<IWebCallResult<Thing>>(r => r.Success == false && (r.Error?.Message.Contains("timed out") ?? false))
    .RetryAsync();