Unfortunately we have some servers with perl 5.6 and 5.8 on them. I want my script to be able to still run with the older versions, but if it is running something newer I want it to use an efficient module. So basically I want to do something like:

if ($] > 5.010) {
  use Super::Cool::Module;
  $supercool = 2;
} elsif (($] <= 5.010) && ($] > 5.008)) {
  use Almost::Cool::Module;
  $supercool = 1;
} elsif ($] <= 5.008) {
  print "No module available for this ancient perl\n";
  $supercool = 0;
## insert code here to duplicate the functionality of the newer module
+s.
}

### then later in the code
if ($supercool == 2) {
# do stuff with the super cool functions

} elsif ($supercool == 1)
# do stuff with the less cool functions

} else {
# 10000 lines of code to implement the super cool functions in ancient
+ perl.

}
[download]

Is this really the best way to go? Just doing this psudocode here looks really messy to maintain.