Re: [TCLCORE] Tcl-Core Digest, Vol 30, Issue 10

[Joe E. <jen...@fl...>]

Donal K. Fellows wrote:
> Twylite wrote:
> > [...]
> > As currently specified you would use "onerror {glob ?emvar? ?optsvar?}",
> > but if you omit emvar/optsvar then you have no access to this
> > information within that handler.
> Sounds acceptable to me. If people want the info, they'll capture it.
> OTOH, they might be quite happy without. [...]

> The only real question is whether
> the msgvar and optvar should be that way round. Pass on that! :-)

Yes, they are in the right order.

[ ... ]

> >>> A modification I find particularly interesting is an alternative
> >>> approach to finally.
> >> I don't like that nearly as much, FWIW.
> > I'd be interested in reasons/insight?
>
> It doesn't feel right. Yeah, I know that's not the strongest of points,
> but I think it's probably based on the fact that most users^Wprogrammers
> are *very* confused by the whole idea of out-of-order execution. They
> find [after] and [fileevent] difficult. [bind] too. :-\

I don't like the alternative approach much either,
simply because it smells too much like innovation.

try/finally as currently proposed is well-established
in other languages and is known to work well.  The
alternative approach certainly sounds interesting
and is probably worth pursuing, but *not for this TIP*.

I want to see this in 8.6.  Now is not the time to
invent brand new untested control flow constructs.


--Joe English