This avoids the temporary, but I'm not sure that it is any better for doing so: 

use strict;
use Data::Dumper;

my $Incoming = 'uno="one" Blah blah dos="two"  * More Noise* tres="thr
+ee"';

my %att= (PREEXISTING=>"val1", ANOTHER=>"Val2");

$att{ uc $_->[ 0 ] } = $_->[ 1 ] for map[
    m[(\w+)="([^"]+)"] 
], $Incoming =~ m[\W*(\w+="[^"]+")]ig;

print Dumper \%att;

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Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: Pair-wise list access - without temp hash by BrowserUk
in thread Pair-wise list access - without temp hash by NetWallah

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