Why does LINQPad dump enum integer values as strings?

c#, linqpad

Solution

Actually, LINQPad is not the culprit here. This is because of an optimization in `Enumerable.Cast`:

    public static IEnumerable<TResult> Cast<TResult>(this IEnumerable source) {
        IEnumerable<TResult> typedSource = source as IEnumerable<TResult>;
        if (typedSource != null) return typedSource;
        if (source == null) throw Error.ArgumentNull("source");
        return CastIterator<TResult>(source);
    }

As you can see, if `source` implements `IEnumerable<TResult>`, then `Cast` just returns the source unchanged. In this case, `source` is of type `Option[]`, which happens to implement `IEnumerable<int>`, so `Cast` returns an array of `Option`, and LINQPad dumps it.

I must admit that it came as a surprise that `Option[]` can be cast to `IEnumerable<int>`, but it seems to be the case...

Problem

I was using LinqPad to test out some Enum functions and I didn't get integers like I expected when I used .Dump(). Why did the ToList() solve the problem? ``` void Main() { Enum.GetValues(typeof(Options)).Cast<int>().Dump(); Enum.GetValues(typeof(Options)).Cast<int>().ToList().Dump(); } public enum Options { Equal, LessThan, GreaterThan } ```

Original source