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=head1 NAME |
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|
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Coro - coroutine process abstraction |
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|
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=head1 SYNOPSIS |
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|
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use Coro; |
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|
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async { |
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# some asynchronous thread of execution |
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}; |
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|
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# alternatively create an async process like this: |
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|
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sub some_func : Coro { |
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# some more async code |
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} |
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|
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yield; |
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|
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=head1 DESCRIPTION |
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|
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=cut |
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|
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package Coro; |
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|
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use Coro::State; |
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|
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use base Exporter; |
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|
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$VERSION = 0.05; |
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|
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@EXPORT = qw(async yield schedule terminate); |
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@EXPORT_OK = qw($current); |
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|
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{ |
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use subs 'async'; |
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|
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my @async; |
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|
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# this way of handling attributes simply is NOT scalable ;() |
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sub import { |
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Coro->export_to_level(1, @_); |
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my $old = *{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"}{CODE}; |
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*{(caller)[0]."::MODIFY_CODE_ATTRIBUTES"} = sub { |
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my ($package, $ref) = (shift, shift); |
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my @attrs; |
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for (@_) { |
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if ($_ eq "Coro") { |
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push @async, $ref; |
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} else { |
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push @attrs, @_; |
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} |
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} |
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return $old ? $old->($package, $name, @attrs) : @attrs; |
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}; |
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} |
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|
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sub INIT { |
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async pop @async while @async; |
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} |
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} |
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|
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=item $main |
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|
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This coroutine represents the main program. |
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|
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=cut |
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|
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our $main = new Coro; |
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|
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=item $current |
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|
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The current coroutine (the last coroutine switched to). The initial value is C<$main> (of course). |
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|
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=cut |
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|
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# maybe some other module used Coro::Specific before... |
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if ($current) { |
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$main->{specific} = $current->{specific}; |
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} |
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|
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our $current = $main; |
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|
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=item $idle |
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|
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The coroutine to switch to when no other coroutine is running. The default |
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implementation prints "FATAL: deadlock detected" and exits. |
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|
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=cut |
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|
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# should be done using priorities :( |
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our $idle = new Coro sub { |
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print STDERR "FATAL: deadlock detected\n"; |
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exit(51); |
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}; |
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|
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# we really need priorities... |
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## my @ready; #d# |
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our @ready = (); # the ready queue. hehe, rather broken ;) |
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|
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# static methods. not really. |
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|
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=head2 STATIC METHODS |
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|
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Static methods are actually functions that operate on the current process only. |
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|
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=over 4 |
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|
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=item async { ... } [@args...] |
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|
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Create a new asynchronous process and return it's process object |
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(usually unused). When the sub returns the new process is automatically |
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terminated. |
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|
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# create a new coroutine that just prints its arguments |
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async { |
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print "@_\n"; |
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} 1,2,3,4; |
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|
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The coderef you submit MUST NOT be a closure that refers to variables |
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in an outer scope. This does NOT work. Pass arguments into it instead. |
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|
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=cut |
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|
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sub async(&@) { |
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my $pid = new Coro @_; |
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$pid->ready; |
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$pid; |
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} |
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|
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=item schedule |
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|
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Calls the scheduler. Please note that the current process will not be put |
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into the ready queue, so calling this function usually means you will |
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never be called again. |
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|
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=cut |
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|
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my $prev; |
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|
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sub schedule { |
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# should be done using priorities :( |
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($prev, $current) = ($current, shift @ready || $idle); |
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Coro::State::transfer($prev, $current); |
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} |
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|
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=item yield |
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|
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Yield to other processes. This function puts the current process into the |
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ready queue and calls C<schedule>. |
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|
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=cut |
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|
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sub yield { |
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$current->ready; |
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&schedule; |
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} |
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|
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=item terminate |
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|
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Terminates the current process. |
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|
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Future versions of this function will allow result arguments. |
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|
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=cut |
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|
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sub terminate { |
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$current->{_results} = [@_]; |
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&schedule; |
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} |
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|
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=back |
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|
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# dynamic methods |
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|
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=head2 PROCESS METHODS |
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|
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These are the methods you can call on process objects. |
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|
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=over 4 |
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|
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=item new Coro \&sub [, @args...] |
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|
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Create a new process and return it. When the sub returns the process |
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automatically terminates. To start the process you must first put it into |
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the ready queue by calling the ready method. |
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|
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The coderef you submit MUST NOT be a closure that refers to variables |
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in an outer scope. This does NOT work. Pass arguments into it instead. |
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|
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=cut |
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|
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sub _newcoro { |
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terminate &{+shift}; |
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} |
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|
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sub new { |
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my $class = shift; |
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bless { |
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_coro_state => (new Coro::State $_[0] && \&_newcoro, @_), |
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}, $class; |
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} |
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|
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=item $process->ready |
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|
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Put the current process into the ready queue. |
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|
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=cut |
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|
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sub ready { |
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push @ready, $_[0]; |
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} |
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|
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=back |
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|
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=cut |
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|
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1; |
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|
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=head1 SEE ALSO |
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|
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L<Coro::Channel>, L<Coro::Cont>, L<Coro::Specific>, L<Coro::Semaphore>, |
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L<Coro::Signal>, L<Coro::State>, L<Coro::Event>. |
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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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|
