Wrong static type in Dump?

mihai

I'm using LINQPad 7 (v7.8.10) side-by-side with 8 beta (v8.8.1) and I'm seeing a difference in the static type that LINQPad prints when calling Enumerable.Range as seen below. According to the docs the static type should be IEnumerable <int> for at least most recent versions of .NET, just as LINQPad 7 prints it.

Is there maybe a glitch with the 8 beta version?

i2van

Looks like type is correct:

Enumerable.Range(3, 5).GetType().Dump();

Latest 8 beta:System.Linq.Enumerable+RangeIterator
Latest 5: System.Linq.Enumerable+<RangeIterator>d__113

Enumerable.Range(3, 5).ToList().GetType().Dump();

Latest 8 beta: System.Collections.Generic.List``1[System.Int32]

sgmoore

Looks to be a framework change/issue

Frameworks 8 and 9 show IList and earlier versions show IEnumerable

Linqpad 7 doesn't fully support Framework 8, but it also shows IList when using a early rc of 8.

i2van

Enumerable.Range(3, 5).GetType().Dump(); shows the same type System.Linq.Enumerable+RangeIterator in 8 latest beta regardless .NET

JoeAlbahari

Run the following with the .NET dropdown set to .NET 7 and then .NET 8:

Environment.Version.Dump();
Enumerable.Range(3, 5).GetType().GetInterfaces().Dump();

You'll see that IList has been added in .NET 8. Note that LINQPad shows the runtime type in the Dump header.

i2van

There are a lot of types listed. Why exactly IList is selected?

JoeAlbahari

It's the most derived (apart from the concrete class, RangeIterator, which is skipped because it's non-public).

i2van

Why not IReadOnlyList? Cause IList is mutable?

JoeAlbahari

If two types are similarly derived, it picks the first in the list. In this case, IList is preferable, so there wasn't a need to special-case this.