$ perl -E'
   use warnings; use strict;
   sub f { my $n="ok"; sub { eval q{$n} } }
   say f->()
'
Variable "$n" is not available at (eval 1) line 2.
Use of uninitialized value in say at -e line 4.


$ perl -E'
   use warnings; use strict;
   sub f { my $n="ok"; sub { $n; eval q{$n} } }
   say f->()
'
Useless use of private variable in void context at -e line 3.
ok

$ perl -E'
   use warnings; use strict;
   sub f { my $n="ok"; sub { $n if 0; eval q{$n} } }
   say f->()
'
ok