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=head1 NAME |
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|
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Coro::Event - do events the coro-way |
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|
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=head1 SYNOPSIS |
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|
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use Coro; |
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use Coro::Event; |
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|
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sub keyboard : Coro { |
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my $w = Coro::Event->io(fd => *STDIN, poll => 'r'); |
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while() { |
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print "cmd> "; |
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my $ev = $w->next; my $cmd = <STDIN>; |
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unloop unless $cmd ne ""; |
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print "data> "; |
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my $ev = $w->next; my $data = <STDIN>; |
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} |
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} |
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|
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&loop; |
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|
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=head1 DESCRIPTION |
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|
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This module enables you to create programs using the powerful Event model |
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(and module), while retaining the linear style known from simple or |
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threaded programs. |
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|
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This module provides a method and a function for every watcher type |
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(I<flavour>) (see L<Event>). The only difference between these and the |
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watcher constructors from Event is that you do not specify a callback |
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function - it will be managed by this module. |
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|
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Your application should just create all necessary coroutines and then call |
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Coro::Event->main. |
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|
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=over 4 |
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|
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=cut |
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|
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package Coro::Event; |
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|
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no warnings; |
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|
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use Carp; |
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|
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use Coro; |
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use Event qw(unloop); # we are re-exporting this, cooool! |
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|
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use base 'Exporter'; |
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|
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@EXPORT = qw(loop unloop sweep); |
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|
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$VERSION = 0.45; |
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|
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=item $w = Coro::Event->flavour(args...) |
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|
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Create and return a watcher of the given type. |
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|
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Examples: |
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|
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my $reader = Coro::Event->io(fd => $filehandle, poll => 'r'); |
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$reader->next; |
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|
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=cut |
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|
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=item $w->next |
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|
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Return the next event of the event queue of the watcher. |
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|
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=cut |
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|
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=item do_flavour(args...) |
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|
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Create a watcher of the given type and immediately call it's next |
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method. This is less efficient then calling the constructor once and the |
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next method often, but it does save typing sometimes. |
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|
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=cut |
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|
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Event->add_hooks(prepare => sub { |
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&Coro::cede while &Coro::nready; |
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1e6; |
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}); |
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|
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sub std_cb { |
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my $w = $_[0]->w; |
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my $q = $w->private; |
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$q->[1] = $_[0]; |
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if ($q->[0]) { # somebody waiting? |
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$q->[0]->ready; |
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} else { |
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$w->stop; |
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} |
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} |
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|
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for my $flavour (qw(idle var timer io signal)) { |
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push @EXPORT, "do_$flavour"; |
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my $new = \&{"Event::$flavour"}; |
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my $class = "Coro::Event::$flavour"; |
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@{"${class}::ISA"} = (Coro::Event::, "Event::$flavour"); |
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my $coronew = sub { |
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# how does one do method-call-by-name? |
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# my $w = $class->SUPER::$flavour(@_); |
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|
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$_[0] eq Coro::Event:: |
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or croak "event constructor \"Coro::Event->$flavour\" must be called as a static method"; |
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|
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my $q = []; # [$coro, $event] |
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my $w = $new->( |
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desc => $flavour, |
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@_, |
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cb => \&std_cb, |
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); |
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$w->private($q); # using private as attribute is pretty useless... |
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bless $w, $class; # reblessing due to broken Event |
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}; |
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*{ $flavour } = $coronew; |
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*{"do_$flavour"} = sub { |
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unshift @_, Coro::Event::; |
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my $e = (&$coronew)->next; |
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$e->w->cancel; |
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$e; |
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}; |
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} |
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|
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sub next { |
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my $w = $_[0]; |
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my $q = $w->private; |
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if ($q->[1]) { # event waiting? |
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$w->again unless $w->is_cancelled; |
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} elsif ($q->[0]) { |
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croak "only one coroutine can wait for an event"; |
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} else { |
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local $q->[0] = $Coro::current; |
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&Coro::schedule; |
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} |
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pop @$q; |
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} |
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|
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=item sweep |
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|
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Similar to Event::one_event and Event::sweep: The idle task is called once |
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(this has the effect of jumping back into the Event loop once to serve new |
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events). |
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|
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The reason this function exists is that you sometimes want to serve events |
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while doing other work. Calling C<Coro::cede> does not work because |
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C<cede> implies that the current coroutine is runnable and does not call |
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into the Event dispatcher. |
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|
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=cut |
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|
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sub sweep { |
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one_event(0); # for now |
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} |
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|
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=item $result = loop([$timeout]) |
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|
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This is the version of C<loop> you should use instead of C<Event::loop> |
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when using this module - it will ensure correct scheduling in the presence |
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of events. |
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|
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=begin comment |
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|
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Unlike loop's counterpart it is not an error when no watchers are active - |
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loop silently returns in this case, as if unloop(undef) were called. |
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|
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=end comment |
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|
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=cut |
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|
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sub loop(;$) { |
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local $Coro::idle = $Coro::current; |
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Coro::schedule; # become idle task, which is implicitly ready |
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&Event::loop; |
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} |
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|
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=item unloop([$result]) |
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|
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Same as Event::unloop (provided here for your convinience only). |
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|
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=cut |
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|
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$Coro::idle = new Coro sub { |
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while () { |
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Event::one_event; # inefficient |
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Coro::schedule; |
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} |
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}; |
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|
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1; |
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|
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=head1 AUTHOR |
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|
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Marc Lehmann <pcg@goof.com> |
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http://www.goof.com/pcg/marc/ |
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|
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=cut |
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|
