I'd change the first one to simply: 
{ $a->{b} = $b || last }

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Jeff japhy Pinyan, P.L., P.M., P.O.D, X.S.: Perl, regex, and perl hacker
How can we ever be the sold short or the cheated, we who for every service have long ago been overpaid? ~~ Meister Eckhart

In reply to Re^2: Shortcut operator for $a->{'b'}=$b if $b; by japhy
in thread Shortcut operator for $a->{'b'}=$b if $b; by rokadave

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