Em Seg, 2009-02-16 às 17:28 +1100, Timothy S. Nelson escreveu:
>       Say I wanted to write a POP3 server.  I want to receive a username and 
> password from the client.  I want things to be interruptable during this, but 
> it's also impossible to sensibly roll things back like they were before the 
> connection was opened.  Is this possible with the concurrency model you 
> specified?

The things you're describing are from the time when we were assuming STM
(Software Transactional Memory) would be used by every implementation of
Perl 6. Things have changed a bit in the last months, as STM seems a bit
more challenging then it looks at first sight for a language as complex
as Perl 6, specially if you think about lazyness.

OTOH, the problem POE solves is the lack of a good "green threads"
implementation in perl 5, which I think is not a problem for Perl 6 (I
can say that for sure about SMOP, but I'm pretty sure that is also valid
for parrot).

In that specific area of writing network servers, I've been with a fixed
idea about providing autothreading code, so you can write code that
looks like 'imperative block-wait programming', but is actually 'async
non-blocking programming'. I'll paste my last sketch about it here:

my $io = Net::TCP.listen(:host<localhost>, :port(1234));
$io does IO::Async[EV];
$io.accepts: -> $conn {
   my %headers;
   my $data;
   my $waiting_headers = 1;
   for =$conn -> $line {
      if ($line && $waiting_headers) {
         my ($name, $val) = split(/\s*:\s*/, $line);
         $headers{$name} = $val;
      } elsif ($line) {
         $data ~= $line;
      } else {
         $waiting_headers = 0;
   $conn.write("200 OK\n\nSucessfull request\n");


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