Re: Type naming conventions: Any_Foo

[Jere <jhb.chat@gmail.com>]

On Saturday, December 7, 2019 at 5:13:24 AM UTC-5, Jeffrey R. Carter wrote:
> On 12/6/19 9:35 PM, Dmitry A. Kazakov wrote:
> 
> > I am required to. There must be always be two types in a GUI, one referential 
> > type and one implementation type. 
> 
> As I have presented here in the past a proof of concept of a GUI library that 
> uses no access types, this is demonstrably false.
> 

You are correct that you can write a high level abstraction wrapper
around a GUI without exposing access types, but to Dmitry's point, the
actual code that creates the GUI components has to use access types
or some sort of referential data type.  Your example GUI illustrates even
this.  When you look at ada_gui.adb, you will see multiple uses of 
access types:  accesses to procedure callbacks, accesses to GUI components,
uses of 'Access, etc. 

So if you are simply writing a wrapper around a GUI library, sure, but if
you are writing an actual GUI library, I'm not sure it can be done without
them.  I would definitely like to see your code if you can write an
actual GUI library without them at all.  The one you have posted on github
still has access types used in it.  You are correct that you can hide 
them at the high level though.