A) It's released with a frozen spec and a large test suite for compliance (https://github.com/perl6/roast), with a compiler available that supports a module ecosystem with over 700 modules (http://modules.perl6.org). What's a complete state in your mind? If not this.

B) All of the below is core language, not a use or import anywhere required. Error reporting is also handled for you without autodie and friends.

  Reading from a file:

  #Efficiently line by line for STDIN
  for lines() -> $line {
      $line.say;
  }

  #Get everything in RAM right now
  my $string = "filename".IO.slurp;

  #Lazy list will do IO as you request into the list
  my @lines = "filename".IO.lines;

  #Listing of directories if the path is a directory
  my @directories = "coolstuff".IO.dir if "coolstuff".IO.d;

  Playing with dates:

  #Get a DateTime for right now
  my $date = DateTime.now;

  #Does what it says on the tin
  say "Yippee" if $date.later(:5years).is-leap-year;