VB.NET silently fails to compile code with `On Error Resume Next` + capturing closures

Question

The following VB.NET console app fails to compile, and VS2022 doesn't show any error / warning:

Module Program
    Sub Main()
        On Error Resume Next                    '0
        Dim a As String
        Dim b = Sub(_a) Console.WriteLine(_a)   '1
        Dim c = Sub(_a) a = _a                  '2
    End Sub
End Module

Commenting out line '0 makes the program work, and so does commenting out '2.

'0 and '1 can work together, but '0 and '2 can't.

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P.S. No need to tell me that On Error Resume Next is not recommended - I wouldn't like to use it. In fact, I personally prefer C# over VB.NET.

I'm just toying with VB to illustrate an idea that Golang-style error handling with if err != nil checks read just like legacy VB-style If Err.GetException() IsNot Nothing Then with On Error Resume Next being active.

Answer 1

I just copied your code and built the project and got this in the Output window:

error BC36595: Method cannot contain both a 'On Error Resume Next' statement and a definition of a variable that is used in a lambda or query expression.

I don't know the inner workings of lambdas well enough to know exactly why that would be an issue but the error message is pretty clear.