in reply to RFC: Defined-Or for before Perl 5.10

H.Merijn Brand used to maintain patches against 5.8.x to enable // and //=. You may want to check his CPAN account to see whether they are still there.

Note that if you want to go the subroutine way, you could also do: 

use List::Util qw[first];
my $val = first {defined} undef, 0;

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Re^2: RFC: Defined-Or for before Perl 5.10
by molecules (Monk) on Oct 29, 2010 at 18:03 UTC

    Thanks!

    The patches are huge, running 350-500K! (c.f. dor-5.8.8-34438.diff)

    He names the patch files starting with "dor". Would that be a better name than "defined_or"?

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      He names the patch files starting with "dor". Would that be a better name than "defined_or"?
      I personally prefer "dor" to "defined_or". Actually, I quite like Larry's original "err" -- though the majority of P5P seemed to prefer "dor", based on some long P5P threads. To be "consistent" with Perl 6, you might even consider "orelse".

      Note that while the // "defined or" operator was added to Perl 5.10, the low precedence version of this operator was not. AFAICT, this low precedence operator morphed from err to dor to orelse; orelse is in Perl 6 as a similar, but not identical, low precedence version of //, but it's not in Perl 5 and I'm not aware of any plans to add it. See also this Larry response on perl6-language mailing list.

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        Actually, IIRC, for quite a while, 5.9.x *had* err, and it was culled not to long before 5.10 came out due to some backwards compatability issues noone seemed to be able to resolve.
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Re^2: RFC: Defined-Or for before Perl 5.10
by Anonymous Monk on Oct 29, 2010 at 18:28 UTC
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