in reply to Using 'sort' to emulate SQL's 'select'...

Why are you using a sort to get the keys? And why the pluses? Pluses are usually used to distinguish between a block of code and a hash, but in this case you don't need the '+' because it'll be considered an anonymous hash anyways... 

my %HoH =
( 1 => { foo => 'bar',
          baz => 'bletch' },
  2 => { foo => 'bar2',
          baz => 'bletch2' },
);

my @fookeys = grep { $HoH{$_}{foo} eq 'bar2' } keys %HoH;
# @fookeys is now 2

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[ ar0n ]

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Re: (ar0n) Re: Using 'sort' to emulate SQL's 'select'...
by deprecated (Priest) on Apr 22, 2001 at 19:51 UTC
    from perldoc perlref: 
               For example, if you wanted a function to make a new
           hash and return a reference to it, you have these
           options:

               sub hashem {        { @_ } }   # silently wrong
               sub hashem {       +{ @_ } }   # ok
               sub hashem { return { @_ } }   # ok

           On the other hand, if you want the other meaning, you
           can do this:

               sub showem {        { @_ } }   # ambiguous (currently o
+k, but may change)
               sub showem {       {; @_ } }   # ok
               sub showem { { return @_ } }   # ok

           The leading +{ and {; always serve to disambiguate the
           expression to mean either the HASH reference, or the
           BLOCK.

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    I use HoH's a lot in my code, so I try to make absolutely sure my hashes are as disambiguated as they can be.

    --
    Laziness, Impatience, Hubris, and Generosity.

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