sub f {a => 1, b=>2}
my %h = (c => 3);
say keys %h, f();
#output:
c
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This is definitely also wrong, say will print the list from f()

D:\>perl -Mfeature=say
sub f {a => 1, b=>2}
my %h = (c => 3);
say keys %h, f();
__END__
ca1b2

D:\>
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