Re: Help: Tagged Types

["chris.danx" <chris.danx@ntlworld.com>]

> > Hi,
> >
> > If we have a decendant of type gwindows.windows.window_type,
gl_window_type,
> > and override it's create procedure, does the following call the create
> > procedure for gwindows.windows.window_type?
>
> No, it dispatches.
>
> You want:
>
>        gwindows.windows.create (gwindows.windows.window_type(window));

Ok.


> Critique of GWindows:
>
> In general, it's best if "create" functions are _not_ primitive
> operations of the type, for precisely this reason. The derived types
> should have a different "create" function, because they will normally
> have additional parameters, and the compiler should help the user call
> the correct one.
>
> One way to do this is to put the Create functions in a local nested
> package.


There were two options:  override create proper or the event on_create.  The
reason for using create was simple, I forgot that on_create could be used
for this.  I'm going to use on_create instead, it's simpler and closer to
what I intend.


Thanks,
Chris