A slight, though still naieve, improvement would be to parse the output of B::Concise for padsv pad ops. Something like this:

use strict;

my $script=shift;
my @output=qx/perl -MO=Concise,-exec $script/;
my $line=1;
my %lexicals;


foreach (@output) {
  if (/nextstate\([\w:]+ \d+ [\w.]+:(\d+)\)/) { $line=$1;next };
  if (/pad[ahs]v\[(.[\w_]+):(\d+),\d+\]/) {
    unless ( exists ( $lexicals{$1}->{$2} ) ) {
      $lexicals{$1}->{$2}=[];
    }
    push @{$lexicals{$1}->{$2}}, $line;
  }
}

foreach (keys %lexicals) {
  if ( scalar (keys %{$lexicals{$_}}) > 1 ) {
    print "Same lexical variable name in different scopes detected:\n"
+;
    print " Variable $_ is used in:\n";
    my $entry=$lexicals{$_};
    print "  Scope $_, line(s) ". join(',',@{$entry->{$_}})."\n" for k
+eys       %$entry;
    print "\n";
  }
}
[download]

When run on a script containing my $camel;{my $camel;my $frog='my $camel';}; this produces:

mymy.pl syntax OK
Same lexical variable name in different scopes detected:
 Variable $camel is used in:
  Scope 1, line(s) 5
  Scope 2, line(s) 7
[download]

As seen, only real lexical declarations are detected, not string literals containing my. I have opted to print all lines containing the variable in the various scopes it appears in, but an easy change would be to just report the first line number it appears in, which should be the guilty declaration.

The code is tested, but it's definitely for fun only :)

Update: Changed regexp to also detect hash and array ops.

CU
Robartes-