Re: Tcl/TK + Ada

[Simon Wright <simon@pushface.org>]

Patrick <patrick@spellingbeewinnars.org> writes:

> So I am working on a daemon that will be written in Ada and controlled
> by a slew of small simple commands. I am planning on controlling it
> through a Tcl/Tk GUI. I am wondering if this is a good design
> decision? Has anyone done somethign like this?
>
> Tcl is not going to be as reliable as Ada but if the code base is
> small (and Tcl was designed for small code bases) then I should be
> okay right?
>
> There is an Ada binding: http://tcladashell.sourceforge.net/index.htm
>
> Am I walking into any pitfalls here...

When you say "daemon" I imagine a process which runs continually, and
needs to be controlled using separate, probably short-lived, processes
run from eg the command line and which interact with the daemon process
using some sort of inter-process comms.

The natural way of writing a TASH/Tk app such as you describe has the
GUI as part of the app, and that's not how daemons work.

Given that, even though I'm one of TclAdaShell (aka TASH)'s maintainers,
I don't see any advantage to writing the control process using
TclAdaShell (aka TASH) vs the web approach, where connecting via a
browser corresponds to the short-lived "process".

I do have a minimal web server EWS[1], but it doesn't hold your hand at
all with connecting web pages via eg AJAX to an Ada application. You can
do it, but it's a lot of work.

In distinction, AWS from AdaCore has a lot of support for this sort of
thing, and is definitely worth a look.

[1] https://sourceforge.net/projects/embed-web-srvr/