On Mon, May 5, 2008 at 1:53 PM, Jerry D. Hedden <[EMAIL PROTECTED]> wrote: > > My sample worked OK *after* I removed the Data::Dumper > > print; apparently, it has some issues w/ circular > > references as well (I tried setting Deepcopy and > > Purity, to no avail); I suspect its due to the fact > > that references to shared elements don't have the same > > stringified value, so it doesn't actually look like > > a circular ref. > > Oh, yes. That's part of what I reported here: > > http://rt.perl.org/rt3/Public/Bug/Display.html?id=37946 > > The following highlights the problem: > > > use strict; > use warnings; > > use threads; > use threads::shared; > > my $x; > $x = \$x; > share($x); > > print("Look at \$x:\n"); > print($x, "\n"); > print($$x, "\n"); > print($$$x, "\n"); > print($$$$x, "\n"); > print($$$$$x, "\n"); > print($$$$$$x, "\n"); > > my @q :shared = ($x); > > my $y = $q[0]; > > print("\nFirst look at \$y:\n"); > print($y, "\n"); > print($$y, "\n"); > print($$$y, "\n"); > print($$$$y, "\n"); > print($$$$$y, "\n"); > print($$$$$$y, "\n"); > > print("\nSecond look at \$y:\n"); > print($y, "\n"); > print($$y, "\n"); > print($$$y, "\n"); > print($$$$y, "\n"); > print($$$$$y, "\n"); > print($$$$$$y, "\n"); > > This outputs: > > Look at $x: > REF(0x144f8f0) > REF(0x144f8f0) > REF(0x144f8f0) > REF(0x144f8f0) > REF(0x144f8f0) > REF(0x144f8f0) > > First look at $y: > SCALAR(0x1423c70) > SCALAR(0x1423ad8) > SCALAR(0x14bd968) > SCALAR(0x14bd980) > SCALAR(0x14bd998) > SCALAR(0x14bd9b0) > > Second look at $y: > REF(0x1423c70) > REF(0x1423ad8) > REF(0x14bd968) > REF(0x14bd980) > REF(0x14bd998) > SCALAR(0x14bd9b0) > > Seems to me that this is a bug. It shows that > threads::shared isn't detecting that it's dealing with a > circular reference. With each level that the app traverses, > threads::shared "unrolls" another version of the shared > variable.
I just posted a patch to blead that fixes this. If the patch passes muster, I'll release an update for threads::shared to CPAN.
