See use and require and also test your code (modified to be "cross-platform").

BEGIN { # need this to happen at compile time
  if ( $^O =~ /some_os_that_does_not_exist/ ) {
    use SomeOSThatDoesNotExist::Facility;
  }
}

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In reply to Re^5: Modules and crossplatform code by Corion
in thread Modules and crossplatform code by Khariton

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