X# Feature: Scoped classes

[wriedmann]

Hello,

it is now the second consecutive day I'm using a language feature that is new to X# (and that maybe most people coming from VO does not knows):

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class MyClass
....
  class MyDetailClass
  ...
  end class

end class

The beauty is that the class MyDetailClass is visibile only in the MyClass itself, and not externally to it.

I'm using that instead of using multidimensional arrays, and I think this makes code much clearer.

Wolfgang

[robert]

Wolfgang,

Yes this works. And you can use both List<MyDetailClass> as well as ARRAY OF MyDetailClass syntax

Robert

[wriedmann]

Hi Robert,

I prefer the array of MyDetailClass because I can use ASort() and AScan() then - I need both.
I know that you don't agree, but ASort() and AScan() as so powerful that I have found no corresponding possibility with the List collection class.

Wolfgang

[wriedmann]

Hi Robert,

in my testclass this works:

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class MyExternalClass
	protect _aData			as array of MyInternalClass

  class MyInternalClass

  	constructor()

  end class

end class

but unfortunately it gives an error in my real code:

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error XS0310: 'clsTechnikerStatistik.TechnikerStatistikDetail' must be a non-abstract type with a public parameterless constructor in order to use it as parameter 'T' in the generic type or method 'XSharp.__ArrayBase<T>'

The class TechnikerStatistikDetail has a public parameterless constructor.....

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class TechnikerStatistikDetail
public constructor()
    self:Aufnr := 0
    return

public property Aufnr as int auto
end class

I'm will try to reproduce this in my sample class.

Wolfgang