This kind of gets me what I'm after without actually dereferencing the stringified referent. The replacement format_arg is "stashing" the stringified data structure while returning its stringified referent 
#!

use Carp::Heavy;
use Data::Dumper;
use Scalar::Util;
use strict;
use warnings;

my @stash;
BEGIN {
    # Now redefine Carp::format_arg so we can dump refs too!
    no warnings qw(once redefine);
    *Carp::format_arg = sub { # shameless stolen from b. d foy
        package Carp;
        my $arg_s=shift;

        my $return_s;
        if (not defined $arg_s) {
            $return_s='undef';
             }
        elsif (Scalar::Util::blessed($arg_s)) { # an object
            $return_s="'".ref($arg_s)."(object/class)'";
             }
        elsif (ref($arg_s)) { # a ref
            require Data::Dumper;
            local $Data::Dumper::Indent=0;
            local $Data::Dumper::Terse=0;
            # deparse CodeRefs
            local $Data::Dumper::Deparse=ref($arg_s) eq 'CODE';
            $return_s=Data::Dumper::Dumper($arg_s);
            $return_s=~ s/^\$VAR\d+\s*=\s*//;
            $return_s=~ s/;\s*$//;
            $return_s=~ s/   */  /g
                if (ref($arg_s) eq 'CODE');
            push(@stash,$return_s);
            $return_s="'$arg_s($#stash)'";
             }
        else {
            $return_s=$arg_s;
            $return_s=~ s/'/\\'/g;
            $return_s=str_len_trim($arg_s,$Carp::Heavy::MaxArgLen);
            $return_s="'$arg_s'" unless $arg_s =~ /^-?[\d.]+\z/;
             }
        $return_s=~ s/([[:cntrl:]]|[[:^ascii:]])/sprintf("\\x{%x}",ord
+($1))/eg;
        return $return_s;
         };
     }; # BEGIN:

$SIG{__WARN__}=sub {
    my $buffer=Carp::longmess();
    print STDOUT "$buffer\n";
    print STDOUT "$_: $stash[$_]\n" for (0..$#stash);
    @stash=();
     };

# Just some code to test
use CGI;
my $q=CGI->new();
main(1,[2],{3=>$q},sub { return "huh" },$q);

sub main {
    warn "main";
    shift; shift;
    subroutine(@_);
     };

sub subroutine {
    warn "sub";
    die "just for fun!";
     };

[download]
It yields:
 
 at Dump.pl line 62
        main::main(1, 'ARRAY(0x1bba4ec)(0)', 'HASH(0x1b58b5c)(1)', 'CO
+DE(0x1a6d4a4)(2)', 'CGI(object/class)') called at Dump.pl line 59

0: [2]
1: {'3' => bless( {'.parameters' => [],'use_tempfile' => 1,'.charset' 
+=> 'ISO-8859-1','.fieldnames' => {},'param' => {},'escape' => 1}, 'CG
+I' )}
2: sub {  use warnings;  use strict 'refs';  return 'huh';}
 at Dump.pl line 68
        main::subroutine('HASH(0x1b58b5c)(0)', 'CODE(0x1a6d4a4)(1)', '
+CGI(object/class)') called at Dump.pl line 64
        main::main(1, 'ARRAY(0x1bba4ec)(2)', 'HASH(0x1b58b5c)(3)', 'CO
+DE(0x1a6d4a4)(4)', 'CGI(object/class)') called at Dump.pl line 59

0: {'3' => bless( {'.parameters' => [],'use_tempfile' => 1,'.charset' 
+=> 'ISO-8859-1','.fieldnames' => {},'param' => {},'escape' => 1}, 'CG
+I' )}
1: sub {  use warnings;  use strict 'refs';  return 'huh';}
2: [2]
3: {'3' => bless( {'.parameters' => [],'use_tempfile' => 1,'.charset' 
+=> 'ISO-8859-1','.fieldnames' => {},'param' => {},'escape' => 1}, 'CG
+I' )}
4: sub {  use warnings;  use strict 'refs';  return 'huh';}
just for fun! at Dump.pl line 69.

[download]

In reply to Re^2: dereferencing a stringfied referent by clueless newbie
in thread dereferencing a stringfied referent by clueless newbie

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