Hi fellow monks,

I want to monitor that a list of CPAN modules are installed and correct versioned on a number of computers. (I intend to to run the script using the excellent GPL'ed tool cfengine www.cfengine.org, but that beside the point.)

Several modules, including CPAN.pm, have a non-numeric version number (i.e. "$VERSION = '1.59_54';"). Without knowing how future versions of modules evolve, how would you create a general version comparison that checks the desired modules are installed in (at least) the version you want?

Sample script: 
#!/usr/bin/perl
use strict;
use warnings;
use ExtUtils::Installed;
use constant TRUE  =>  0;
use constant FALSE => -1;
use constant DEBUG =>  1;
my $params = shift;  # cfengine sends params as single string
my ($modulename, $requiredversion) = split(' ', $params);
die "missing modulename!" unless $modulename;

my $instmod = ExtUtils::Installed->new();
foreach my $module ((grep /^$modulename$/, $instmod->modules())) {
   my $version = $instmod->version($module);
   if ($version >= $requiredversion){
     print STDERR "$modulename installed:$version required:$requiredve
+rsion - ok\n" if DEBUG;
     exit(TRUE);  # installed and in correct version
   } else {
     print STDERR "$modulename installed:$version required:$requiredve
+rsion - failed\n" if DEBUG;
     exit(FALSE); # installed, but not correct version
   }
}
print STDERR "$modulename not installed - failed\n" if DEBUG;
exit(FALSE); # false
__END__

[download]
# ./cpanModVer.pl HTML::Mason 1.1
HTML::Mason installed:1.23 required:1.1 - ok
# ./cpanModVer.pl CPAN 1.0
Argument "1.59_54" isn't numeric in numeric ge (>=) at ./cpanModVer.pl
+ line 36.

[download]
Linux 2.4.20-28.7 i686 This is perl, v5.6.1 built for i386-linux (GNU cfengine 2.1.7p1)

In reply to General version comparison of CPAN modules by andreas1234567

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