perl 備註，如何知道這個模組已安裝，及它的版本是多少

sub isModuleInstalled($) {
 my $module = shift;
 my $true = 1;
 my $false = not $true;
 eval( 'use ' . $module );
 if ($@) {
      print $module. " is not installed\n";
      return $false;
 } else {
      print $module. " is already installed\n";
      return $true;
 }
}

sub isModuleVersion($) {
 my $module = shift;
 my $true = 1;
 my $false = not $true;
 eval( 'use ' . $module );
 if ($@) {
      print $module. " is not installed\n";
      return $false;
 } else {
      print $module. " is already installed\n";
      eval "require $module";
      if($@) {
          return $false;
      } else {
          return $module->VERSION;
      }
 }
}