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in reply to Something eq hashref key

I'm not sure I fully understand your question, maybe you could provide a few more examples of what should be true and what should be false, but are you perhaps looking for exists? As in: if ( exists $fields->{field1} )

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Re^2: Something eq hashref key
by LanX (Saint) on Mar 25, 2019 at 14:06 UTC
    On a side note, it's a pity we can't use exists on hash slices ...

      DB<9> exists @h{"a","z"}
exists argument is not a HASH or ARRAY element or a subroutine at (eva
+l 18)...

    [download]

    Cheers Rolf
    (addicted to the Perl Programming Language :)
    Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

[reply]
[d/l]

      In a recent thread it was shown that hash slices are not faster than maps, exists on hash slices is not needed. 

      sub slex { my $h = shift; return map { exists $h->{$_} || 0 } @_ }

my %h = map { $_ => 1 } 'a'..'t';
my @bool = slex \%h, 'a'..'z';
print "@bool\n";

      [download]
[reply]
[d/l]
[select]
        You must be joking! (?)

        The benchmark was about non intuitive performance of constant lists.

        Slices are 5 times faster than maps in this example, and the overhead of join is still included

        Cheers Rolf
        (addicted to the Perl Programming Language :)
        Wikisyntax for the Monastery FootballPerl is like chess, only without the dice

[reply]
Re^2: Something eq hashref key
by Anonymous Monk on Mar 25, 2019 at 13:51 UTC
    Thank you so much, haukex.

    Yes, "exists" is what I was looking for.

    Thank you for the enlightenment :))
[reply]

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