eval EXPR is capable of accessing lexicals.

my $t = 'test';
print eval '$t';  # test
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As long as it can "see" them (i.e. As long as they are in scope)

my $t1 = 'test1';
sub show { print eval "\$$_" for @_; }
my $t2 = 'test2';
show(qw( t1 t2 ));  # test1, but not test2
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It can't see a variable that no longer exists.

{
   my $t = 'test';
   sub show { print eval "\$$_" for @_; }
}
show(qw( t ));  # Nothing
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It can't see a variable that is no longer in scope.

{
   my $t = 'test';
   sub foo { $t }
   sub show { print eval "\$$_" for @_; }
}
show(qw( t ));  # Nothing
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...unless the function with the eval EXPR captured it.

{
   my $t = 'test';
   sub show { $t; print eval "\$$_" for @_; }
}
show(qw( t ));  # test
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Anyway, why aren't you passing the variable's value instead of its name?