I would have upvoted more than once if I could. I'm pretty sure to never do something like that (I still never add to use attributes, and the very few times I used prototypes were on named subroutines) but it was an interesting read nonetheless!

But you could avoid the issue altogether, and in my opinion get a clearer code by setting the prototype or attribute after the declaration:

use Sub::Util qw/set_prototype/;
(*Hello, *Hi) = map { set_prototype '\@\@' => $_ } map { my $var = $_;
+ sub { $_; } } qw/Hello Hi/;
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I also thought about

use attributes();
sub Hi { "Hi" };
attributes::->import(__PACKAGE__, *{$_}{CODE}, 'prototype(\@\@)') for 
+*Hi;
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but I can't test it with v5.14 (which doesn't have prototype attributes), and it does not work with the 'lvalue' attribute:

use v5.14;
use attributes();
use Data::Dumper;

my $Hi;
sub Hi:lvalue {
  $Hi;
}

my $Hello;
sub Hello {
  $Hello;
}

BEGIN { attributes::->import(__PACKAGE__, \&Hello, 'lvalue'); }

Hi = 'monks'; # It kind of looks like a sigil-less variable actually :
+) 
Hello = 'world'; # There would be a warning here without the BEGIN blo
+ck
say "Hi: ", Hi;
say "Hello: ", Hello;
__END__
Hi: monks
Hello:
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