Seems to be the case that named hash lookups are (marginally, but consistently) quicker:

{ 
    my $ref = { 1 .. 1e6 }; 
    my %h = 1 .. 1e6; 
    cmpthese -5,{
        a => sub{ exists $ref->{$_} and 1 for 1 .. 1e6; },
        b => sub{ exists $h{$_}     and 1 for 1 .. 1e6; }
    }
};;
    Rate   a   b
a 1.24/s  -- -3%
b 1.28/s  3%  --

    Rate   a   b
a 1.36/s  -- -5%
b 1.43/s  5%  --

    Rate   a   b
a 1.24/s  -- -3%
b 1.28/s  3%  --

    Rate   a   b
a 1.23/s  -- -5%
b 1.29/s  5%  --

    Rate   a   b
a 1.27/s  -- -3%
b 1.30/s  3%  --

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In reply to Re^3: Faster Hash Slices by BrowserUk
in thread Faster Hash Slices by jht

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