[ViewVC] Diff of: cvs/AnyEvent-MP/MP.pm

Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.48 by root, Thu Aug 13 02:59:42 2009 UTC vs.
Revision 1.61 by root, Mon Aug 24 08:06:49 2009 UTC

…		…
22	# sending messages	22	# sending messages
23	snd $port, type => data...;	23	snd $port, type => data...;
24	snd $port, @msg;	24	snd $port, @msg;
25	snd @msg_with_first_element_being_a_port;	25	snd @msg_with_first_element_being_a_port;
26		26
27	# creating/using miniports	27	# creating/using ports, the simple way
28	my $miniport = port { my @msg = @_; 0 };	28	my $simple_port = port { my @msg = @_; 0 };
29		29
30	# creating/using full ports	30	# creating/using ports, tagged message matching
31	my $port = port;	31	my $port = port;
32	rcv $port, smartmatch => $cb->(@msg);
33	rcv $port, ping => sub { snd $_[0], "pong"; 0 };	32	rcv $port, ping => sub { snd $_[0], "pong"; 0 };
34	rcv $port, pong => sub { warn "pong received\n"; 0 };	33	rcv $port, pong => sub { warn "pong received\n"; 0 };
35
36	# more, smarter, matches (_any_ is exported by this module)
37	rcv $port, [child_died => $pid] => sub { ...
38	rcv $port, [_any_, _any_, 3] => sub { .. $_[2] is 3
39		34
40	# create a port on another node	35	# create a port on another node
41	my $port = spawn $node, $initfunc, @initdata;	36	my $port = spawn $node, $initfunc, @initdata;
42		37
43	# monitoring	38	# monitoring
…		…
74		69
75	=item port	70	=item port
76		71
77	A port is something you can send messages to (with the C<snd> function).	72	A port is something you can send messages to (with the C<snd> function).
78		73
79	Some ports allow you to register C<rcv> handlers that can match specific	74	Ports allow you to register C<rcv> handlers that can match all or just
80	messages. All C<rcv> handlers will receive messages they match, messages	75	some messages. Messages will not be queued.
81	will not be queued.
82		76
83	=item port id - C<noderef#portname>	77	=item port id - C<noderef#portname>
84		78
85	A port id is normaly the concatenation of a noderef, a hash-mark (C<#>) as	79	A port ID is the concatenation of a noderef, a hash-mark (C<#>) as
86	separator, and a port name (a printable string of unspecified format). An	80	separator, and a port name (a printable string of unspecified format). An
87	exception is the the node port, whose ID is identical to its node	81	exception is the the node port, whose ID is identical to its node
88	reference.	82	reference.
89		83
90	=item node	84	=item node
91		85
92	A node is a single process containing at least one port - the node	86	A node is a single process containing at least one port - the node port,
93	port. You can send messages to node ports to find existing ports or to	87	which provides nodes to manage each other remotely, and to create new
94	create new ports, among other things.	88	ports.
95		89
96	Nodes are either private (single-process only), slaves (connected to a	90	Nodes are either private (single-process only), slaves (connected to a
97	master node only) or public nodes (connectable from unrelated nodes).	91	master node only) or public nodes (connectable from unrelated nodes).
98		92
99	=item noderef - C<host:port,host:port...>, C<id@noderef>, C<id>	93	=item noderef - C<host:port,host:port...>, C<id@noderef>, C<id>
…		…
132	use base "Exporter";	126	use base "Exporter";
133		127
134	our $VERSION = $AnyEvent::MP::Kernel::VERSION;	128	our $VERSION = $AnyEvent::MP::Kernel::VERSION;
135		129
136	our @EXPORT = qw(	130	our @EXPORT = qw(
137	NODE $NODE *SELF node_of _any_	131	NODE $NODE *SELF node_of after
138	resolve_node initialise_node	132	resolve_node initialise_node
139	snd rcv mon kil reg psub spawn	133	snd rcv mon mon_guard kil reg psub spawn
140	port	134	port
141	);	135	);
142		136
143	our $SELF;	137	our $SELF;
144		138
…		…
148	kil $SELF, die => $msg;	142	kil $SELF, die => $msg;
149	}	143	}
150		144
151	=item $thisnode = NODE / $NODE	145	=item $thisnode = NODE / $NODE
152		146
153	The C<NODE> function returns, and the C<$NODE> variable contains	147	The C<NODE> function returns, and the C<$NODE> variable contains the
154	the noderef of the local node. The value is initialised by a call	148	noderef of the local node. The value is initialised by a call to
155	to C<become_public> or C<become_slave>, after which all local port	149	C<initialise_node>.
156	identifiers become invalid.
157		150
158	=item $noderef = node_of $port	151	=item $noderef = node_of $port
159		152
160	Extracts and returns the noderef from a portid or a noderef.	153	Extracts and returns the noderef from a port ID or a noderef.
161		154
162	=item initialise_node $noderef, $seednode, $seednode...	155	=item initialise_node $noderef, $seednode, $seednode...
163		156
164	=item initialise_node "slave/", $master, $master...	157	=item initialise_node "slave/", $master, $master...
165		158
…		…
168	it should know the noderefs of some other nodes in the network.	161	it should know the noderefs of some other nodes in the network.
169		162
170	This function initialises a node - it must be called exactly once (or	163	This function initialises a node - it must be called exactly once (or
171	never) before calling other AnyEvent::MP functions.	164	never) before calling other AnyEvent::MP functions.
172		165
173	All arguments are noderefs, which can be either resolved or unresolved.	166	All arguments (optionally except for the first) are noderefs, which can be
		167	either resolved or unresolved.
		168
		169	The first argument will be looked up in the configuration database first
		170	(if it is C<undef> then the current nodename will be used instead) to find
		171	the relevant configuration profile (see L<aemp>). If none is found then
		172	the default configuration is used. The configuration supplies additional
		173	seed/master nodes and can override the actual noderef.
174		174
175	There are two types of networked nodes, public nodes and slave nodes:	175	There are two types of networked nodes, public nodes and slave nodes:
176		176
177	=over 4	177	=over 4
178		178
179	=item public nodes	179	=item public nodes
180		180
181	For public nodes, C<$noderef> must either be a (possibly unresolved)	181	For public nodes, C<$noderef> (supplied either directly to
182	noderef, in which case it will be resolved, or C<undef> (or missing), in	182	C<initialise_node> or indirectly via a profile or the nodename) must be a
183	which case the noderef will be guessed.	183	noderef (possibly unresolved, in which case it will be resolved).
184		184
185	Afterwards, the node will bind itself on all endpoints and try to connect	185	After resolving, the node will bind itself on all endpoints and try to
186	to all additional C<$seednodes> that are specified. Seednodes are optional	186	connect to all additional C<$seednodes> that are specified. Seednodes are
187	and can be used to quickly bootstrap the node into an existing network.	187	optional and can be used to quickly bootstrap the node into an existing
		188	network.
188		189
189	=item slave nodes	190	=item slave nodes
190		191
191	When the C<$noderef> is the special string C<slave/>, then the node will	192	When the C<$noderef> (either as given or overriden by the config file)
		193	is the special string C<slave/>, then the node will become a slave
192	become a slave node. Slave nodes cannot be contacted from outside and will	194	node. Slave nodes cannot be contacted from outside and will route most of
193	route most of their traffic to the master node that they attach to.	195	their traffic to the master node that they attach to.
194		196
195	At least one additional noderef is required: The node will try to connect	197	At least one additional noderef is required (either by specifying it
196	to all of them and will become a slave attached to the first node it can	198	directly or because it is part of the configuration profile): The node
197	successfully connect to.	199	will try to connect to all of them and will become a slave attached to the
		200	first node it can successfully connect to.
		201
		202	Note that slave nodes cannot change their name, and consequently, their
		203	master, so if the master goes down, the slave node will not function well
		204	anymore until it can re-establish conenciton to its master. This makes
		205	slave nodes unsuitable for long-term nodes or fault-tolerant networks.
198		206
199	=back	207	=back
200		208
201	This function will block until all nodes have been resolved and, for slave	209	This function will block until all nodes have been resolved and, for slave
202	nodes, until it has successfully established a connection to a master	210	nodes, until it has successfully established a connection to a master
203	server.	211	server.
204		212
		213	All the seednodes will also be specially marked to automatically retry
		214	connecting to them infinitely.
		215
205	Example: become a public node listening on the default node.	216	Example: become a public node listening on the guessed noderef, or the one
		217	specified via C<aemp> for the current node. This should be the most common
		218	form of invocation for "daemon"-type nodes.
206		219
207	initialise_node;	220	initialise_node;
		221
		222	Example: become a slave node to any of the the seednodes specified via
		223	C<aemp>. This form is often used for commandline clients.
		224
		225	initialise_node "slave/";
		226
		227	Example: become a slave node to any of the specified master servers. This
		228	form is also often used for commandline clients.
		229
		230	initialise_node "slave/", "master1", "192.168.13.17", "mp.example.net";
208		231
209	Example: become a public node, and try to contact some well-known master	232	Example: become a public node, and try to contact some well-known master
210	servers to become part of the network.	233	servers to become part of the network.
211		234
212	initialise_node undef, "master1", "master2";	235	initialise_node undef, "master1", "master2";
…		…
215		238
216	initialise_node 4041;	239	initialise_node 4041;
217		240
218	Example: become a public node, only visible on localhost port 4044.	241	Example: become a public node, only visible on localhost port 4044.
219		242
220	initialise_node "locahost:4044";	243	initialise_node "localhost:4044";
221
222	Example: become a slave node to any of the specified master servers.
223
224	initialise_node "slave/", "master1", "192.168.13.17", "mp.example.net";
225		244
226	=item $cv = resolve_node $noderef	245	=item $cv = resolve_node $noderef
227		246
228	Takes an unresolved node reference that may contain hostnames and	247	Takes an unresolved node reference that may contain hostnames and
229	abbreviated IDs, resolves all of them and returns a resolved node	248	abbreviated IDs, resolves all of them and returns a resolved node
…		…
266	=item snd $port, type => @data	285	=item snd $port, type => @data
267		286
268	=item snd $port, @msg	287	=item snd $port, @msg
269		288
270	Send the given message to the given port ID, which can identify either	289	Send the given message to the given port ID, which can identify either
271	a local or a remote port, and can be either a string or soemthignt hat	290	a local or a remote port, and must be a port ID.
272	stringifies a sa port ID (such as a port object :).
273		291
274	While the message can be about anything, it is highly recommended to use a	292	While the message can be about anything, it is highly recommended to use a
275	string as first element (a portid, or some word that indicates a request	293	string as first element (a port ID, or some word that indicates a request
276	type etc.).	294	type etc.).
277		295
278	The message data effectively becomes read-only after a call to this	296	The message data effectively becomes read-only after a call to this
279	function: modifying any argument is not allowed and can cause many	297	function: modifying any argument is not allowed and can cause many
280	problems.	298	problems.
…		…
285	that Storable can serialise and deserialise is allowed, and for the local	303	that Storable can serialise and deserialise is allowed, and for the local
286	node, anything can be passed.	304	node, anything can be passed.
287		305
288	=item $local_port = port	306	=item $local_port = port
289		307
290	Create a new local port object that can be used either as a pattern	308	Create a new local port object and returns its port ID. Initially it has
291	matching port ("full port") or a single-callback port ("miniport"),	309	no callbacks set and will throw an error when it receives messages.
292	depending on how C<rcv> callbacks are bound to the object.
293		310
294	=item $port = port { my @msg = @_; $finished }	311	=item $local_port = port { my @msg = @_ }
295		312
296	Creates a "miniport", that is, a very lightweight port without any pattern	313	Creates a new local port, and returns its ID. Semantically the same as
297	matching behind it, and returns its ID. Semantically the same as creating
298	a port and calling C<rcv $port, $callback> on it.	314	creating a port and calling C<rcv $port, $callback> on it.
299		315
300	The block will be called for every message received on the port. When the	316	The block will be called for every message received on the port, with the
301	callback returns a true value its job is considered "done" and the port	317	global variable C<$SELF> set to the port ID. Runtime errors will cause the
302	will be destroyed. Otherwise it will stay alive.	318	port to be C<kil>ed. The message will be passed as-is, no extra argument
		319	(i.e. no port ID) will be passed to the callback.
303		320
304	The message will be passed as-is, no extra argument (i.e. no port id) will	321	If you want to stop/destroy the port, simply C<kil> it:
305	be passed to the callback.
306		322
307	If you need the local port id in the callback, this works nicely:	323	my $port = port {
308		324	my @msg = @_;
309	my $port; $port = port {	325	...
310	snd $otherport, reply => $port;	326	kil $SELF;
311	};	327	};
312		328
313	=cut	329	=cut
314		330
315	sub rcv($@);	331	sub rcv($@);
		332
		333	sub _kilme {
		334	die "received message on port without callback";
		335	}
316		336
317	sub port(;&) {	337	sub port(;&) {
318	my $id = "$UNIQ." . $ID++;	338	my $id = "$UNIQ." . $ID++;
319	my $port = "$NODE#$id";	339	my $port = "$NODE#$id";
320		340
321	if (@_) {	341	rcv $port, shift \|\| \&_kilme;
322	rcv $port, shift;
323	} else {
324	$PORT{$id} = sub { }; # nop
325	}
326		342
327	$port	343	$port
328	}	344	}
329		345
330	=item reg $port, $name
331
332	=item reg $name
333
334	Registers the given port (or C<$SELF><<< if missing) under the name
335	C<$name>. If the name already exists it is replaced.
336
337	A port can only be registered under one well known name.
338
339	A port automatically becomes unregistered when it is killed.
340
341	=cut
342
343	sub reg(@) {
344	my $port = @_ > 1 ? shift : $SELF \|\| Carp::croak 'reg: called with one argument only, but $SELF not set,';
345
346	$REG{$_[0]} = $port;
347	}
348
349	=item rcv $port, $callback->(@msg)	346	=item rcv $local_port, $callback->(@msg)
350		347
351	Replaces the callback on the specified miniport (after converting it to	348	Replaces the default callback on the specified port. There is no way to
352	one if required).	349	remove the default callback: use C<sub { }> to disable it, or better
353		350	C<kil> the port when it is no longer needed.
354	=item rcv $port, tagstring => $callback->(@msg), ...
355
356	=item rcv $port, $smartmatch => $callback->(@msg), ...
357
358	=item rcv $port, [$smartmatch...] => $callback->(@msg), ...
359
360	Register callbacks to be called on matching messages on the given full
361	port (after converting it to one if required) and return the port.
362
363	The callback has to return a true value when its work is done, after
364	which is will be removed, or a false value in which case it will stay
365	registered.
366		351
367	The global C<$SELF> (exported by this module) contains C<$port> while	352	The global C<$SELF> (exported by this module) contains C<$port> while
368	executing the callback.	353	executing the callback. Runtime errors during callback execution will
		354	result in the port being C<kil>ed.
369		355
370	Runtime errors during callback execution will result in the port being	356	The default callback received all messages not matched by a more specific
371	C<kil>ed.	357	C<tag> match.
372		358
373	If the match is an array reference, then it will be matched against the	359	=item rcv $local_port, tag => $callback->(@msg_without_tag), ...
374	first elements of the message, otherwise only the first element is being
375	matched.
376		360
377	Any element in the match that is specified as C<_any_> (a function	361	Register (or replace) callbacks to be called on messages starting with the
378	exported by this module) matches any single element of the message.	362	given tag on the given port (and return the port), or unregister it (when
		363	C<$callback> is C<$undef> or missing). There can only be one callback
		364	registered for each tag.
379		365
380	While not required, it is highly recommended that the first matching	366	The original message will be passed to the callback, after the first
381	element is a string identifying the message. The one-string-only match is	367	element (the tag) has been removed. The callback will use the same
382	also the most efficient match (by far).	368	environment as the default callback (see above).
383		369
384	Example: create a port and bind receivers on it in one go.	370	Example: create a port and bind receivers on it in one go.
385		371
386	my $port = rcv port,	372	my $port = rcv port,
387	msg1 => sub { ...; 0 },	373	msg1 => sub { ... },
388	msg2 => sub { ...; 0 },	374	msg2 => sub { ... },
389	;	375	;
390		376
391	Example: create a port, bind receivers and send it in a message elsewhere	377	Example: create a port, bind receivers and send it in a message elsewhere
392	in one go:	378	in one go:
393		379
394	snd $otherport, reply =>	380	snd $otherport, reply =>
395	rcv port,	381	rcv port,
396	msg1 => sub { ...; 0 },	382	msg1 => sub { ... },
397	...	383	...
398	;	384	;
		385
		386	Example: temporarily register a rcv callback for a tag matching some port
		387	(e.g. for a rpc reply) and unregister it after a message was received.
		388
		389	rcv $port, $otherport => sub {
		390	my @reply = @_;
		391
		392	rcv $SELF, $otherport;
		393	};
399		394
400	=cut	395	=cut
401		396
402	sub rcv($@) {	397	sub rcv($@) {
403	my $port = shift;	398	my $port = shift;
404	my ($noderef, $portid) = split /#/, $port, 2;	399	my ($noderef, $portid) = split /#/, $port, 2;
405		400
406	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}	401	$NODE{$noderef} == $NODE{""}
407	or Carp::croak "$port: rcv can only be called on local ports, caught";	402	or Carp::croak "$port: rcv can only be called on local ports, caught";
408		403
409	if (@_ == 1) {	404	while (@_) {
		405	if (ref $_[0]) {
		406	if (my $self = $PORT_DATA{$portid}) {
		407	"AnyEvent::MP::Port" eq ref $self
		408	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
		409
		410	$self->[2] = shift;
		411	} else {
410	my $cb = shift;	412	my $cb = shift;
411	delete $PORT_DATA{$portid};
412	$PORT{$portid} = sub {	413	$PORT{$portid} = sub {
413	local $SELF = $port;	414	local $SELF = $port;
414	eval {	415	eval { &$cb }; _self_die if $@;
415	&$cb	416	};
416	and kil $port;
417	};	417	}
418	_self_die if $@;	418	} elsif (defined $_[0]) {
419	};
420	} else {
421	my $self = $PORT_DATA{$portid} \|\|= do {	419	my $self = $PORT_DATA{$portid} \|\|= do {
422	my $self = bless {	420	my $self = bless [$PORT{$port} \|\| sub { }, { }, $port], "AnyEvent::MP::Port";
423	id => $port,
424	}, "AnyEvent::MP::Port";
425		421
426	$PORT{$portid} = sub {	422	$PORT{$portid} = sub {
427	local $SELF = $port;	423	local $SELF = $port;
428		424
429	eval {
430	for (@{ $self->{rc0}{$_[0]} }) {	425	if (my $cb = $self->[1]{$_[0]}) {
431	$_ && &{$_->[0]}	426	shift;
432	&& undef $_;	427	eval { &$cb }; _self_die if $@;
433	}	428	} else {
434
435	for (@{ $self->{rcv}{$_[0]} }) {
436	$_ && [@_[1 .. @{$_->[1]}]] ~~ $_->[1]
437	&& &{$_->[0]}	429	&{ $self->[0] };
438	&& undef $_;
439	}
440
441	for (@{ $self->{any} }) {
442	$_ && [@_[0 .. $#{$_->[1]}]] ~~ $_->[1]
443	&& &{$_->[0]}
444	&& undef $_;
445	}	430	}
446	};	431	};
447	_self_die if $@;	432
		433	$self
448	};	434	};
449		435
450	$self
451	};
452
453	"AnyEvent::MP::Port" eq ref $self	436	"AnyEvent::MP::Port" eq ref $self
454	or Carp::croak "$port: rcv can only be called on message matching ports, caught";	437	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
455		438
456	while (@_) {
457	my ($match, $cb) = splice @_, 0, 2;	439	my ($tag, $cb) = splice @_, 0, 2;
458		440
459	if (!ref $match) {	441	if (defined $cb) {
460	push @{ $self->{rc0}{$match} }, [$cb];	442	$self->[1]{$tag} = $cb;
461	} elsif (("ARRAY" eq ref $match && !ref $match->[0])) {
462	my ($type, @match) = @$match;
463	@match
464	? push @{ $self->{rcv}{$match->[0]} }, [$cb, \@match]
465	: push @{ $self->{rc0}{$match->[0]} }, [$cb];
466	} else {	443	} else {
467	push @{ $self->{any} }, [$cb, $match];	444	delete $self->[1]{$tag};
468	}	445	}
469	}	446	}
470	}	447	}
471		448
472	$port	449	$port
…		…
527	will arrive, or the monitoring action will be invoked after possible	504	will arrive, or the monitoring action will be invoked after possible
528	message loss has been detected. No messages will be lost "in between"	505	message loss has been detected. No messages will be lost "in between"
529	(after the first lost message no further messages will be received by the	506	(after the first lost message no further messages will be received by the
530	port). After the monitoring action was invoked, further messages might get	507	port). After the monitoring action was invoked, further messages might get
531	delivered again.	508	delivered again.
		509
		510	Note that monitoring-actions are one-shot: once released, they are removed
		511	and will not trigger again.
532		512
533	In the first form (callback), the callback is simply called with any	513	In the first form (callback), the callback is simply called with any
534	number of C<@reason> elements (no @reason means that the port was deleted	514	number of C<@reason> elements (no @reason means that the port was deleted
535	"normally"). Note also that I<< the callback B<must> never die >>, so use	515	"normally"). Note also that I<< the callback B<must> never die >>, so use
536	C<eval> if unsure.	516	C<eval> if unsure.
…		…
697	my $id = "$RUNIQ." . $ID++;	677	my $id = "$RUNIQ." . $ID++;
698		678
699	$_[0] =~ /::/	679	$_[0] =~ /::/
700	or Carp::croak "spawn init function must be a fully-qualified name, caught";	680	or Carp::croak "spawn init function must be a fully-qualified name, caught";
701		681
702	($NODE{$noderef} \|\| add_node $noderef)	682	snd_to_func $noderef, "AnyEvent::MP::_spawn" => $id, @_;
703	->send (["", "AnyEvent::MP::_spawn" => $id, @_]);
704		683
705	"$noderef#$id"	684	"$noderef#$id"
706	}	685	}
707		686
708	=back	687	=item after $timeout, @msg
709		688
710	=head1 NODE MESSAGES	689	=item after $timeout, $callback
711		690
712	Nodes understand the following messages sent to them. Many of them take	691	Either sends the given message, or call the given callback, after the
713	arguments called C<@reply>, which will simply be used to compose a reply	692	specified number of seconds.
714	message - C<$reply[0]> is the port to reply to, C<$reply[1]> the type and
715	the remaining arguments are simply the message data.
716		693
717	While other messages exist, they are not public and subject to change.	694	This is simply a utility function that come sin handy at times.
718		695
719	=over 4
720
721	=cut	696	=cut
722		697
723	=item lookup => $name, @reply	698	sub after($@) {
		699	my ($timeout, @action) = @_;
724		700
725	Replies with the port ID of the specified well-known port, or C<undef>.	701	my $t; $t = AE::timer $timeout, 0, sub {
726		702	undef $t;
727	=item devnull => ...	703	ref $action[0]
728		704	? $action[0]()
729	Generic data sink/CPU heat conversion.	705	: snd @action;
730		706	};
731	=item relay => $port, @msg	707	}
732
733	Simply forwards the message to the given port.
734
735	=item eval => $string[ @reply]
736
737	Evaluates the given string. If C<@reply> is given, then a message of the
738	form C<@reply, $@, @evalres> is sent.
739
740	Example: crash another node.
741
742	snd $othernode, eval => "exit";
743
744	=item time => @reply
745
746	Replies the the current node time to C<@reply>.
747
748	Example: tell the current node to send the current time to C<$myport> in a
749	C<timereply> message.
750
751	snd $NODE, time => $myport, timereply => 1, 2;
752	# => snd $myport, timereply => 1, 2, <time>
753		708
754	=back	709	=back
755		710
756	=head1 AnyEvent::MP vs. Distributed Erlang	711	=head1 AnyEvent::MP vs. Distributed Erlang
757		712
…		…
776	convenience functionality.	731	convenience functionality.
777		732
778	This means that AEMP requires a less tightly controlled environment at the	733	This means that AEMP requires a less tightly controlled environment at the
779	cost of longer node references and a slightly higher management overhead.	734	cost of longer node references and a slightly higher management overhead.
780		735
		736	=item * Erlang has a "remote ports are like local ports" philosophy, AEMP
		737	uses "local ports are like remote ports".
		738
		739	The failure modes for local ports are quite different (runtime errors
		740	only) then for remote ports - when a local port dies, you I<know> it dies,
		741	when a connection to another node dies, you know nothing about the other
		742	port.
		743
		744	Erlang pretends remote ports are as reliable as local ports, even when
		745	they are not.
		746
		747	AEMP encourages a "treat remote ports differently" philosophy, with local
		748	ports being the special case/exception, where transport errors cannot
		749	occur.
		750
781	=item * Erlang uses processes and a mailbox, AEMP does not queue.	751	=item * Erlang uses processes and a mailbox, AEMP does not queue.
782		752
783	Erlang uses processes that selctively receive messages, and therefore	753	Erlang uses processes that selectively receive messages, and therefore
784	needs a queue. AEMP is event based, queuing messages would serve no useful	754	needs a queue. AEMP is event based, queuing messages would serve no
785	purpose.	755	useful purpose. For the same reason the pattern-matching abilities of
		756	AnyEvent::MP are more limited, as there is little need to be able to
		757	filter messages without dequeing them.
786		758
787	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).	759	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).
788		760
789	=item * Erlang sends are synchronous, AEMP sends are asynchronous.	761	=item * Erlang sends are synchronous, AEMP sends are asynchronous.
790		762
791	Sending messages in Erlang is synchronous and blocks the process. AEMP	763	Sending messages in Erlang is synchronous and blocks the process (and
792	sends are immediate, connection establishment is handled in the	764	so does not need a queue that can overflow). AEMP sends are immediate,
793	background.	765	connection establishment is handled in the background.
794		766
795	=item * Erlang can silently lose messages, AEMP cannot.	767	=item * Erlang suffers from silent message loss, AEMP does not.
796		768
797	Erlang makes few guarantees on messages delivery - messages can get lost	769	Erlang makes few guarantees on messages delivery - messages can get lost
798	without any of the processes realising it (i.e. you send messages a, b,	770	without any of the processes realising it (i.e. you send messages a, b,
799	and c, and the other side only receives messages a and c).	771	and c, and the other side only receives messages a and c).
800		772
…		…
812	eventually be killed - it cannot happen that a node detects a port as dead	784	eventually be killed - it cannot happen that a node detects a port as dead
813	and then later sends messages to it, finding it is still alive.	785	and then later sends messages to it, finding it is still alive.
814		786
815	=item * Erlang can send messages to the wrong port, AEMP does not.	787	=item * Erlang can send messages to the wrong port, AEMP does not.
816		788
817	In Erlang it is quite possible that a node that restarts reuses a process	789	In Erlang it is quite likely that a node that restarts reuses a process ID
818	ID known to other nodes for a completely different process, causing	790	known to other nodes for a completely different process, causing messages
819	messages destined for that process to end up in an unrelated process.	791	destined for that process to end up in an unrelated process.
820		792
821	AEMP never reuses port IDs, so old messages or old port IDs floating	793	AEMP never reuses port IDs, so old messages or old port IDs floating
822	around in the network will not be sent to an unrelated port.	794	around in the network will not be sent to an unrelated port.
823		795
824	=item * Erlang uses unprotected connections, AEMP uses secure	796	=item * Erlang uses unprotected connections, AEMP uses secure

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Comparing AnyEvent-MP/MP.pm (file contents): Revision 1.48 by root, Thu Aug 13 02:59:42 2009 UTC vs. Revision 1.61 by root, Mon Aug 24 08:06:49 2009 UTC

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Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.48 by root, Thu Aug 13 02:59:42 2009 UTC vs.
Revision 1.61 by root, Mon Aug 24 08:06:49 2009 UTC