Ada requires too much typing!
in [ADA]
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From: Jeffrey R. Carter on 11 Jun 2010 14:03 Stephen Leake wrote: > Georg Bauhaus <rm.dash-bauhaus(a)futureapps.de> writes: > >> Will it, in theory, be possible to write a Qt-like library >> in Ada such that client programs declare variables like >> >> W : Some_Window'Class := Some_Lib_Pack.Make (Typ => Some_Id); >> >> That is, programs do not use access Some_Window'Class? > > No. Because the underlying C++ uses pointers, so the Ada has to as well. In the implementation, sure. But the question was about the client; I suspect it would be possible to design the binding so the client need not use pointers. -- Jeff Carter "We burst our pimples at you." Monty Python & the Holy Grail 16
From: Simon Wright on 11 Jun 2010 14:38 "Randy Brukardt" <randy(a)rrsoftware.com> writes: > declare > My_Window : Claw.Basic_Window.Window; > begin > Global_Window.Replace_Element (Root_Window_Type'Class(My_Window)); > end; So Claw.Basic_Window.Window isn't limited? Not immediately clear what the semantics of copying a window are (absent any knowledge of Claw!)
From: Randy Brukardt on 28 Jun 2010 22:13
"Simon Wright" <simon(a)pushface.org> wrote in message news:m2typ92z53.fsf(a)pushface.org... > "Randy Brukardt" <randy(a)rrsoftware.com> writes: > >> declare >> My_Window : Claw.Basic_Window.Window; >> begin >> Global_Window.Replace_Element (Root_Window_Type'Class(My_Window)); >> end; > > So Claw.Basic_Window.Window isn't limited? > > Not immediately clear what the semantics of copying a window are (absent > any knowledge of Claw!) Right, it's not limited. In Claw, a window object provides a view of a window; there can be multiple views (via assignment, function return, or the like). Operations on a view generally are applied to the window itself (such as being moved or closed). If the last view of a window is finalized, then the window itself is destroyed. The advantage of non-limited windows should be fairly obvious: it's possible to pass a window as a parameter and save it somewhere. This is especially useful for passing windows to tasks at start-up (each task can have it's own window to write into). None of this requires any explicit access types as the client level - Claw itself manages these as needed. And that means no explicit storage management is needed, either. Randy, |