[Proposal]: Mark methods of Microsoft.VisualBasic.Information module with [Extension]

[VBAndCs]

Based on #546, #547 I suggest to:

1. Mark methods of Microsoft.VisualBasic.Information module with the ExtensionAttribute.
2. Make the compiler look at this special module first to resolve extension methods for objects if they are not members of the type itself, ignoring Option Strict On and any current limitations due to late binding. After all this is only one intrinsic module containing object-related jobs. SO, we can write:

   If x.IsDbNull Then

3. Add some more useful functions to the module to shorten object checks syntax, such as IsSomething or HasValueor alike as proposed in I propose we add Something keyword #546.

   If x.HasValue Then

[AdamSpeight2008]

@VBAndCs Maybe also raise the issue on the runtime repo.

https://github.com/dotnet/runtime/issues

[VBAndCs]

It is a VB.NET issue, since it needs a special treatment of the compiler.
There is also the issue when the object is Nothing. The workaround is to use the ? operator:
If x?.IsDbNull
I think we should not need the ? since this is an extension method, but I don't know how the compiler acts in this case in runtime.

[pricerc]

It is a VB.NET issue, since it needs a special treatment of the compiler.
There is also the issue when the object is Nothing. The workaround is to use the ? operator:
If x?.IsDbNull
I think we should not need the ? since this is an extension method, but I don't know how the compiler acts in this case in runtime.

hmmm. I like how you're thinking here, but....

dim haveValue = x.IsDbNull

vs

dim haveValue = x?.IsDbNull

what's the correct response in each case if x is nothing ?