use 5.032001;
use warnings;

#use Data::Dumper;
use PPI;
use PPR::X;
#use PPI::Dumper;
use Scalar::Util qw(blessed);

my $PTR;
my @PACKAGE=('main','main');
    # Just a useful routine during delousing
    sub as_header {
        my $string=(' > ' x $PTR).ref shift;
        return $string.('='x (64-length $string));
        };

sub process_chunk {
    $PACKAGE[++$PTR]=undef;
    for my $node (shift->children) {
        next # This should never happen!
            unless (blessed $node);
        next # WE don't care about these do we??
            if ($node->isa('PPI::Statement::Null') || $node->isa('PPI::Token::Comment')
            || $node->isa('PPI::Token::Whitespace') || $node->isa('PPI::Token::Structure'));

        #say as_header($node);
        if ($node->isa('PPI::Structure::Block'))  {
            #say $node->content;
            }
        elsif ($node->isa('PPI::Statement::Package')) {
            #say $node->content;
            #say $node->child(2)->content;
            $PACKAGE[$PTR]=$node->child(2)->content;
            }
        elsif ($node->isa('PPI::Statement::Sub')) {
            #say $node->content;
            my $name=$node->child(2)->content;
            unless ($name =~ m{::}) {
                for (my $i=$PTR; $i >= 0; $i--) {
                    if (defined $PACKAGE[$i]) {
                        $name=qq{$PACKAGE[$i]::$name};#'
                        last;
                        };
                    };
                };
            say $name;
            }
        else {
            #PPI::Dumper->new($node,whitespace=>0)->print;
            };
        # See if further processing is possible
        process_chunk($node)
            if (blessed $node && $node->can('children'));
        }
    $PTR--;
    }; # sub process_chunk:

my $chunk=do {
    local $/;
    <DATA>
    };

# Let's let Conway confirm all is good to go!
unless ($chunk =~ m{ (?&PerlEntireDocument) $PPR::X::GRAMMAR }x) {
    die "Invalid Perl code: " . $PPR::X::ERROR->source . "\n"
    }
else {
    # Now go process the bloody thing!
    process_chunk(PPI::Document->new(\$chunk));
    };
__DATA__
    sub zero { # main::zero
        say __PACKAGE__.q{::zero};
        };
    package Fee;
    sub one { # Fee::one
        say __PACKAGE__.q{::one};
        };
    package Fi;
    sub two { # Fi::two
        say __PACKAGE__.q{::two};
        };
    { package Fo;
        sub three { # Foo::Three
            say __PACKAGE__.q{::three};
            };
        }; # End of package Foo!
    {;
        say "This block introduces no new package"
        };
    sub Fum::four { # Fum::four
        say __PACKAGE__.q{:four};
        };
    sub four { # Fi::four
        say __PACKAGE__.q{:four};
        };
    package I_smell_the_blood_of_an_Englishman { # Package with a block
        sub five { # I_smell_the_blood_of_an_Englishman::five
            say qq{Fee-fi-fo-fum,\nI smell the blood of an Englishman,\nBe he alive, or be he dead\nI'll grind his bones to make my bread.};
            };
        };