unless ($perl) {
        my $candidate = File::Spec->catfile($CPAN::iCwd,$^X);
        $^X = $perl = $candidate if MM->maybe_command($candidate);
    }
    unless ($perl) {
        my ($component,$perl_name);
      DIST_PERLNAME: foreach $perl_name ($^X, 'perl', 'perl5', "perl$]") {
          PATH_COMPONENT: foreach $component (File::Spec->path(),
                                                $Config::Config{'binexp'}) {
                next unless defined($component) && $component;
                my($abs) = File::Spec->catfile($component,$perl_name);
                if (MM->maybe_command($abs)) {
                    $^X = $perl = $abs;
                    last DIST_PERLNAME;
                }
            }
        }
    }
    return $perl;
}


#-> sub CPAN::exists ;
sub exists {
    my($mgr,$class,$id) = @_;
    CPAN::HandleConfig->load unless $CPAN::Config_loaded++;
    CPAN::Index->reload;
    ### Carp::croak "exists called without class argument" unless $class;
    $id ||= "";
    $id =~ s/:+/::/g if $class eq "CPAN::Module";
    my $exists;
    if (CPAN::_sqlite_running) {
        $exists = (exists $META->{readonly}{$class}{$id} or
                   $CPAN::SQLite->set($class, $id));
    } else {
        $exists =  exists $META->{readonly}{$class}{$id};
    }
    $exists ||= exists $META->{readwrite}{$class}{$id}; # unsafe meta access, ok
}

#-> sub CPAN::delete ;
sub delete {
  my($mgr,$class,$id) = @_;
  delete $META->{readonly}{$class}{$id}; # unsafe meta access, ok
  delete $META->{readwrite}{$class}{$id}; # unsafe meta access, ok
}

#-> sub CPAN::has_usable
# has_inst is sometimes too optimistic, we should replace it with this
# has_usable whenever a case is given
sub has_usable {
    my($self,$mod,$message) = @_;
    return 1 if $HAS_USABLE->{$mod};
    my $has_inst = $self->has_inst($mod,$message);
    return unless $has_inst;
    my $usable;
    $usable = {
               LWP => [ # we frequently had "Can't locate object
                        # method "new" via package "LWP::UserAgent" at
                        # (eval 69) line 2006
                       sub {require LWP},
                       sub {require LWP::UserAgent},
                       sub {require HTTP::Request},
                       sub {require URI::URL},
                      ],
               'Net::FTP' => [
                            sub {require Net::FTP},
                            sub {require Net::Config},
                           ],
               'File::HomeDir' => [
                                   sub {require File::HomeDir;
                                        unless (CPAN::Version->vge(File::HomeDir::->VERSION, 0.52)) {
                                            for ("Will not use File::HomeDir, need 0.52\n") {
                                                $CPAN::Frontend->mywarn($_);
                                                die $_;
                                            }
                                        }
                                    },
                                  ],
               'Archive::Tar' => [
                                  sub {require Archive::Tar;
                                       unless (CPAN::Version->vge(Archive::Tar::->VERSION, 1.00)) {
                                            for ("Will not use Archive::Tar, need 1.00\n") {
                                                $CPAN::Frontend->mywarn($_);
                                                die $_;
                                            }
                                       }
                                  },
                                 ],
               'File::Temp' => [
                                # XXX we should probably delete from
                                # %INC too so we can load after we
                                # installed a new enough version --
                                # I'm not sure.
                                sub {require File::Temp;
                                     unless (CPAN::Version->vge(File::Temp::->VERSION,0.16)) {
                                         for ("Will not use File::Temp, need 0.16\n") {
                                                $CPAN::Frontend->mywarn($_);
                                                die $_;
                                         }