3 ms·

I love Perl. Perl is my language of choice. So I promise that I am not trolling. Let's just stipulate that I'm slow or inexperienced or very confused. What is

• chromatic 17y ago
  The example defines a subtype which represents a file on disk. Any parameter conforming to that subtype must name a file that is present on disk. Think of this subtype as a named precondition -- it's a concise, intention-revealing way of reporting error conditions without cluttering the internals of the function with duplicate error-handling code.
  • telemachos 17y ago
    Nicely explained. Thanks.