}
    }
    my $in_loop = 0;
    for my $i (0..$#deps) {
        my $x = $deps[$i]{name};
        $in_loop ||= $x eq $loop_starts_with;
        my $xo = CPAN::Shell->expandany($x) or next;
        if ($xo->isa("CPAN::Module")) {
            my $have = $xo->inst_version || "N/A";
            my($want,$d,$want_type);
            if ($i>0 and $d = $deps[$i-1]{name}) {
                my $do = CPAN::Shell->expandany($d);
                $want = $do->{prereq_pm}{requires}{$x};
                if (defined $want) {
                    $want_type = "requires: ";
                } else {
                    $want = $do->{prereq_pm}{build_requires}{$x};
                    if (defined $want) {
                        $want_type = "build_requires: ";
                    } else {
                        $want_type = "unknown status";
                        $want = "???";
                    }
                }
            } else {
                $want = $xo->cpan_version;
                $want_type = "want: ";
            }
            $deps[$i]{have} = $have;
            $deps[$i]{want_type} = $want_type;
            $deps[$i]{want} = $want;
            $deps[$i]{display_as} = "$x (have: $have; $want_type$want)";
        } elsif ($xo->isa("CPAN::Distribution")) {
            $deps[$i]{display_as} = $xo->pretty_id;
            if ($in_loop) {
                $xo->{make} = CPAN::Distrostatus->new("NO cannot resolve circular dependency");
            } else {
                $xo->{make} = CPAN::Distrostatus->new("NO one dependency ($loop_starts_with) is a circular dependency");

            }
            $xo->store_persistent_state; # otherwise I will not reach
                                         # all involved parties for
                                         # the next session
        }
    }
    bless { deps => \@deps }, $class;
}

sub as_string {
    my($self) = shift;
    my $ret = "\nRecursive dependency detected:\n    ";
    $ret .= join("\n => ", map {$_->{display_as}} @{$self->{deps}});
    $ret .= ".\nCannot resolve.\n";
    $ret;
}

package CPAN::Exception::yaml_not_installed;
use strict;
use overload '""' => "as_string";

sub new {
    my($class,$module,$file,$during) = @_;
    bless { module => $module, file => $file, during => $during }, $class;
}

sub as_string {
    my($self) = shift;
    "'$self->{module}' not installed, cannot $self->{during} '$self->{file}'\n";
}

package CPAN::Exception::yaml_process_error;
use strict;
use overload '""' => "as_string";

sub new {
    my($class,$module,$file,$during,$error) = @_;
    # my $at = Carp::longmess(""); # XXX find something more beautiful
    bless { module => $module,
            file => $file,
            during => $during,
            error => $error,
            # at => $at,
          }, $class;
}

sub as_string {
    my($self) = shift;
    if ($self->{during}) {
        if ($self->{file}) {
            if ($self->{module}) {
                if ($self->{error}) {
                    return "Alert: While trying to '$self->{during}' YAML file\n".
                        " '$self->{file}'\n".
                            "with '$self->{module}' the following error was encountered:\n".
                                "  $self->{error}\n";
                } else {
                    return "Alert: While trying to '$self->{during}' YAML file\n".
                        " '$self->{file}'\n".
                            "with '$self->{module}' some unknown error was encountered\n";
                }
            } else {