[RESOLVED] Namespace Resolution

[pacerier]

if my class library is called LIBB and within LIBB i have a class MyClass

So within MyClass i have a member called LIBB as well. how do i refer to LIBB (class library) from anywhere within MyClass. if i'd typed LIBB it would refer to the member instead of the class library.


No i do not have a name clash right now, i was just wondering how would it be done.

[dbasnett]

    Dim foobar As New foo
    foobar.bar=?

Class foo
    Class bar

    End Class
End Class

[techgnome]

since to get to the member, you specify the class, it's kind of moot... however... this is a good reason why naming members after types is a generally avoided practice (except in C#, which is case sensitive, so your type "IsLikeThis" and the member would be "isLikeThis").

-tg

[pacerier]

totally agree, but anyway i was just trying to solve the problem. its something like this:

Namespace LIBB
 
    Public Class Class1
        Dim a As LIBB.Class2 '<-- Undefined
        Public Class LIBB
 
        End Class
        Public Class Class2
 
        End Class
    End Class
 
    Public Class Class2 ' <-- I cannot access this class
 
    End Class
 
End Namespace

[Shaggy Hiker]

Of course not. You have two different Class2 in the same file. How would the compiler know which one you want? Just because one is defined within a different class makes no real difference in this case. One is shadowing the other.

The bottom line is this: Name collision happens. That's one of the reasons behind having classes, and is the only reason behind having namespaces. Still, it doesn't preclude poor name choices resulting in name collisions, and there is no way around that. At some point, you have to take responsibility for naming things in ways that don't conflict. There are conventions that help restrict the possible conflicts, but you can still cause those conflicts, and when you do, you should realize that the idea is a bad one, not the language. After all, it is technically impossible to have a 'complete' language, which is one that has no invalid constructs.

[pacerier]

orh, i was hoping for something like relative positions since every member must belong to one parent just like how every file must belong to one folder. so it will be something like this:

 Dim a As <root>.<root>.Class2

[Shaggy Hiker]

Yeah, that's nearly the case. Unfortunately, declaring a public class within a class doesn't resolve the way you are hoping it would, and that prevents the construction you are trying for. Personally, I would prefer if it was done the way you were expecting, because as it is there is no justification that I can see for declaring a public class within a different class. Declaring it Private does have an impact, though.

You could probably get something close to what you are looking at with nested namespaces, but not with nested classes.

[techgnome]

there is no justification that I can see for declaring a public class within a different class.

And yet, that is exactly how types datasets are designed. The typed datatable is a class inside the typed dataset. And to get to it, I use the NS.DS.DT .... then again, we're not dealing with an inner class that has the same name as an outer class in that case.

-tg

[pacerier]

actually i first had this problem when i was trying to imitate the existing namespaces into my class library.

So basically i had something like this:

Namespace MyLibrary
    Namespace System
        Namespace Windows
            Namespace Forms
            End Namespace
        End Namespace
        Public Class [Enum]
        End Class
        Public Class Math
        End Class
    End Namespace
End Namespace

and somewhere in MyLibrary.System.Math i would wish to refer to the real System.Math but couldn't find a way to do so.

de temporary solution i had was to rename System to Sys, which of course is what i did only because i do not have a choice.

[Shaggy Hiker]

There is a way to alias a name. Since you have your own system, you might want to alias the actual system inside MyLibrary. I have never used aliasing, and am not sure that it is possible, but it would be something like Using System As OuterSystem, or some such.

[techgnome]

You can alias if you IMPORT a namespace:

Imports M = Namespace.Namespace2.namespace3.anothersnamespace.assembly

Then to get to any of the classes in "M" you use M like any other namespace:

Dim myMClass As New M.MClass

-tg

[pacerier]

dat's something cool, thanks = )

[techgnome]

I use it a lot when dealing with things from Infragistics, which is notorious for their endless namespacing. Some one once referred to it as the Infragistics Ultra Megazord WinGrid.

-tg