(I didn't think to respond to this until I saw a later response from dlux.) Ken Fox wrote: > > try transaction { > ... > } > > That's a really interesting extension to exceptions -- code that has > no side-effects unless it finishes. Well, maybe transaction-enabling variables could help one achieve this, but it would not be an automatic result. I mean, in my $x = 0; sub side { $x = 1; } trans { side(); die; }; print "x=$x\n"; # should print 1, yes? # side-effect achieved, despite having occurred inside # a trans block. I don't believe $x should have been transaction-enabled here. That would just be a major problem. No, the semantics of trans should be much more constrained. Tacking it onto the mechanics of C<local> seems much more straightforward, I think. $x = 0; sub side { $x = 1; } trans { local $x; side(); print "x=$x\n"; # should print 1 die; } print "x=$x\n"; # should print 0 Personally, I'd rather see transaction-enabling requested on a per-variable basis. -- John Porter We're building the house of the future together.
- Re: RFC 130 (v4) Transaction-enabled variables for Perl6 John Porter
- Re: RFC 130 (v4) Transaction-enabled variables for ... dLux
- Re: RFC 130 (v4) Transaction-enabled variables ... Steve Fink
- Re: RFC 130 (v4) Transaction-enabled variab... Jarkko Hietaniemi
- Re: RFC 130 (v4) Transaction-enabled va... Dan Sugalski
- Re: RFC 130 (v4) Transaction-enabled variab... John Porter
- Re: RFC 130 (v4) Transaction-enabled variab... Chaim Frenkel
- Re: RFC 130 (v4) Transaction-enabled va... Ken Fox
- Re: RFC 130 (v4) Transaction-enabl... John Porter
- Re: RFC 130 (v4) Transaction-enabl... dLux
- Re: RFC 130 (v4) Transaction-enabl... John Porter
- Re: RFC 130 (v4) Transaction-enabl... dLux
- Re: RFC 130 (v4) Transaction-enabl... Chaim Frenkel
- Re: RFC 130 (v4) Transaction-enabl... Ken Fox
- Re: RFC 130 (v4) Transaction-enabl... Chaim Frenkel
- Re: RFC 130 (v4) Transaction-enabl... dLux
- Re: RFC 130 (v4) Transaction-enabl... Dan Sugalski
- Re: RFC 130 (v4) Transaction-enabl... dLux
- Re: RFC 130 (v4) Transaction-enabl... Bart Lateur
- Re: RFC 130 (v4) Transaction-enabl... Jarkko Hietaniemi
- Re: RFC 130 (v4) Transaction-enabl... Chaim Frenkel