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

Comparing cvsroot/AnyEvent-MP/MP.pm (file contents):
Revision 1.49 by root, Thu Aug 13 15:29:58 2009 UTC vs.
Revision 1.63 by root, Thu Aug 27 21:29:37 2009 UTC

…		…
11	NODE $port # returns the noderef of the port	11	NODE $port # returns the noderef of the port
12		12
13	$SELF # receiving/own port id in rcv callbacks	13	$SELF # receiving/own port id in rcv callbacks
14		14
15	# initialise the node so it can send/receive messages	15	# initialise the node so it can send/receive messages
16	initialise_node; # -OR-	16	initialise_node;
17	initialise_node "localhost:4040"; # -OR-
18	initialise_node "slave/", "localhost:4040"
19		17
20	# ports are message endpoints	18	# ports are message endpoints
21		19
22	# sending messages	20	# sending messages
23	snd $port, type => data...;	21	snd $port, type => data...;
24	snd $port, @msg;	22	snd $port, @msg;
25	snd @msg_with_first_element_being_a_port;	23	snd @msg_with_first_element_being_a_port;
26		24
27	# creating/using miniports	25	# creating/using ports, the simple way
28	my $miniport = port { my @msg = @_; 0 };	26	my $simple_port = port { my @msg = @_; 0 };
29		27
30	# creating/using full ports	28	# creating/using ports, tagged message matching
31	my $port = port;	29	my $port = port;
32	rcv $port, smartmatch => $cb->(@msg);
33	rcv $port, ping => sub { snd $_[0], "pong"; 0 };	30	rcv $port, ping => sub { snd $_[0], "pong"; 0 };
34	rcv $port, pong => sub { warn "pong received\n"; 0 };	31	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		32
40	# create a port on another node	33	# create a port on another node
41	my $port = spawn $node, $initfunc, @initdata;	34	my $port = spawn $node, $initfunc, @initdata;
42		35
43	# monitoring	36	# monitoring
…		…
74		67
75	=item port	68	=item port
76		69
77	A port is something you can send messages to (with the C<snd> function).	70	A port is something you can send messages to (with the C<snd> function).
78		71
79	Some ports allow you to register C<rcv> handlers that can match specific	72	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	73	some messages. Messages will not be queued.
81	will not be queued.
82		74
83	=item port id - C<noderef#portname>	75	=item port ID - C<noderef#portname>
84		76
85	A port id is normaly the concatenation of a noderef, a hash-mark (C<#>) as	77	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	78	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	79	exception is the the node port, whose ID is identical to its node
88	reference.	80	reference.
89		81
90	=item node	82	=item node
91		83
92	A node is a single process containing at least one port - the node	84	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	85	which provides nodes to manage each other remotely, and to create new
94	create new ports, among other things.	86	ports.
95		87
96	Nodes are either private (single-process only), slaves (connected to a	88	Nodes are either private (single-process only), slaves (can only talk to
97	master node only) or public nodes (connectable from unrelated nodes).	89	public nodes, but do not need an open port) or public nodes (connectable
		90	from any other node).
98		91
99	=item noderef - C<host:port,host:port...>, C<id@noderef>, C<id>	92	=item node ID - C<[a-za-Z0-9_\-.:]+>
100		93
101	A node reference is a string that either simply identifies the node (for	94	A node ID is a string that either simply identifies the node (for
102	private and slave nodes), or contains a recipe on how to reach a given	95	private and slave nodes), or contains a recipe on how to reach a given
103	node (for public nodes).	96	node (for public nodes).
104		97
105	This recipe is simply a comma-separated list of C<address:port> pairs (for	98	This recipe is simply a comma-separated list of C<address:port> pairs (for
106	TCP/IP, other protocols might look different).	99	TCP/IP, other protocols might look different).
…		…
132	use base "Exporter";	125	use base "Exporter";
133		126
134	our $VERSION = $AnyEvent::MP::Kernel::VERSION;	127	our $VERSION = $AnyEvent::MP::Kernel::VERSION;
135		128
136	our @EXPORT = qw(	129	our @EXPORT = qw(
137	NODE $NODE *SELF node_of _any_	130	NODE $NODE *SELF node_of after
138	resolve_node initialise_node	131	resolve_node initialise_node
139	snd rcv mon kil reg psub spawn	132	snd rcv mon mon_guard kil reg psub spawn
140	port	133	port
141	);	134	);
142		135
143	our $SELF;	136	our $SELF;
144		137
…		…
148	kil $SELF, die => $msg;	141	kil $SELF, die => $msg;
149	}	142	}
150		143
151	=item $thisnode = NODE / $NODE	144	=item $thisnode = NODE / $NODE
152		145
153	The C<NODE> function returns, and the C<$NODE> variable contains	146	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	147	node id 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	148	C<initialise_node>.
156	identifiers become invalid.
157		149
158	=item $noderef = node_of $port	150	=item $nodeid = node_of $port
159		151
160	Extracts and returns the noderef from a portid or a noderef.	152	Extracts and returns the noderef from a port ID or a node ID.
161		153
162	=item initialise_node $noderef, $seednode, $seednode...	154	=item initialise_node $profile_name
163
164	=item initialise_node "slave/", $master, $master...
165		155
166	Before a node can talk to other nodes on the network it has to initialise	156	Before a node can talk to other nodes on the network it has to initialise
167	itself - the minimum a node needs to know is it's own name, and optionally	157	itself - the minimum a node needs to know is it's own name, and optionally
168	it should know the noderefs of some other nodes in the network.	158	it should know the noderefs of some other nodes in the network.
169		159
…		…
187		177
188	For public nodes, C<$noderef> (supplied either directly to	178	For public nodes, C<$noderef> (supplied either directly to
189	C<initialise_node> or indirectly via a profile or the nodename) must be a	179	C<initialise_node> or indirectly via a profile or the nodename) must be a
190	noderef (possibly unresolved, in which case it will be resolved).	180	noderef (possibly unresolved, in which case it will be resolved).
191		181
192	After resolving, the node will bind itself on all endpoints and try to	182	After resolving, the node will bind itself on all endpoints.
193	connect to all additional C<$seednodes> that are specified. Seednodes are	183
		184	=item slave nodes
		185
		186	When the C<$noderef> (either as given or overriden by the config file)
		187	is the special string C<slave/>, then the node will become a slave
		188	node. Slave nodes cannot be contacted from outside, and cannot talk to
		189	each other (at least in this version of AnyEvent::MP).
		190
		191	Slave nodes work by creating connections to all public nodes, using the
		192	L<AnyEvent::MP::Global> service.
		193
		194	=back
		195
		196	After initialising itself, the node will connect to all additional
		197	C<$seednodes> that are specified diretcly or via a profile. Seednodes are
194	optional and can be used to quickly bootstrap the node into an existing	198	optional and can be used to quickly bootstrap the node into an existing
195	network.	199	network.
196		200
197	=item slave nodes	201	All the seednodes will also be specially marked to automatically retry
198		202	connecting to them indefinitely, so make sure that seednodes are really
199	When the C<$noderef> (either as given or overriden by the config file)	203	reliable and up (this might also change in the future).
200	is the special string C<slave/>, then the node will become a slave
201	node. Slave nodes cannot be contacted from outside and will route most of
202	their traffic to the master node that they attach to.
203
204	At least one additional noderef is required (either by specifying it
205	directly or because it is part of the configuration profile): The node
206	will try to connect to all of them and will become a slave attached to the
207	first node it can successfully connect to.
208
209	=back
210
211	This function will block until all nodes have been resolved and, for slave
212	nodes, until it has successfully established a connection to a master
213	server.
214		204
215	Example: become a public node listening on the guessed noderef, or the one	205	Example: become a public node listening on the guessed noderef, or the one
216	specified via C<aemp> for the current node. This should be the most common	206	specified via C<aemp> for the current node. This should be the most common
217	form of invocation for "daemon"-type nodes.	207	form of invocation for "daemon"-type nodes.
218		208
…		…
221	Example: become a slave node to any of the the seednodes specified via	211	Example: become a slave node to any of the the seednodes specified via
222	C<aemp>. This form is often used for commandline clients.	212	C<aemp>. This form is often used for commandline clients.
223		213
224	initialise_node "slave/";	214	initialise_node "slave/";
225		215
226	Example: become a slave node to any of the specified master servers. This
227	form is also often used for commandline clients.
228
229	initialise_node "slave/", "master1", "192.168.13.17", "mp.example.net";
230
231	Example: become a public node, and try to contact some well-known master	216	Example: become a public node, and try to contact some well-known master
232	servers to become part of the network.	217	servers to become part of the network.
233		218
234	initialise_node undef, "master1", "master2";	219	initialise_node undef, "master1", "master2";
235		220
…		…
284	=item snd $port, type => @data	269	=item snd $port, type => @data
285		270
286	=item snd $port, @msg	271	=item snd $port, @msg
287		272
288	Send the given message to the given port ID, which can identify either	273	Send the given message to the given port ID, which can identify either
289	a local or a remote port, and can be either a string or soemthignt hat	274	a local or a remote port, and must be a port ID.
290	stringifies a sa port ID (such as a port object :).
291		275
292	While the message can be about anything, it is highly recommended to use a	276	While the message can be about anything, it is highly recommended to use a
293	string as first element (a portid, or some word that indicates a request	277	string as first element (a port ID, or some word that indicates a request
294	type etc.).	278	type etc.).
295		279
296	The message data effectively becomes read-only after a call to this	280	The message data effectively becomes read-only after a call to this
297	function: modifying any argument is not allowed and can cause many	281	function: modifying any argument is not allowed and can cause many
298	problems.	282	problems.
…		…
303	that Storable can serialise and deserialise is allowed, and for the local	287	that Storable can serialise and deserialise is allowed, and for the local
304	node, anything can be passed.	288	node, anything can be passed.
305		289
306	=item $local_port = port	290	=item $local_port = port
307		291
308	Create a new local port object that can be used either as a pattern	292	Create a new local port object and returns its port ID. Initially it has
309	matching port ("full port") or a single-callback port ("miniport"),	293	no callbacks set and will throw an error when it receives messages.
310	depending on how C<rcv> callbacks are bound to the object.
311		294
312	=item $port = port { my @msg = @_; $finished }	295	=item $local_port = port { my @msg = @_ }
313		296
314	Creates a "miniport", that is, a very lightweight port without any pattern	297	Creates a new local port, and returns its ID. Semantically the same as
315	matching behind it, and returns its ID. Semantically the same as creating
316	a port and calling C<rcv $port, $callback> on it.	298	creating a port and calling C<rcv $port, $callback> on it.
317		299
318	The block will be called for every message received on the port. When the	300	The block will be called for every message received on the port, with the
319	callback returns a true value its job is considered "done" and the port	301	global variable C<$SELF> set to the port ID. Runtime errors will cause the
320	will be destroyed. Otherwise it will stay alive.	302	port to be C<kil>ed. The message will be passed as-is, no extra argument
		303	(i.e. no port ID) will be passed to the callback.
321		304
322	The message will be passed as-is, no extra argument (i.e. no port id) will	305	If you want to stop/destroy the port, simply C<kil> it:
323	be passed to the callback.
324		306
325	If you need the local port id in the callback, this works nicely:	307	my $port = port {
326		308	my @msg = @_;
327	my $port; $port = port {	309	...
328	snd $otherport, reply => $port;	310	kil $SELF;
329	};	311	};
330		312
331	=cut	313	=cut
332		314
333	sub rcv($@);	315	sub rcv($@);
		316
		317	sub _kilme {
		318	die "received message on port without callback";
		319	}
334		320
335	sub port(;&) {	321	sub port(;&) {
336	my $id = "$UNIQ." . $ID++;	322	my $id = "$UNIQ." . $ID++;
337	my $port = "$NODE#$id";	323	my $port = "$NODE#$id";
338		324
339	if (@_) {	325	rcv $port, shift \|\| \&_kilme;
340	rcv $port, shift;
341	} else {
342	$PORT{$id} = sub { }; # nop
343	}
344		326
345	$port	327	$port
346	}	328	}
347		329
348	=item reg $port, $name
349
350	=item reg $name
351
352	Registers the given port (or C<$SELF><<< if missing) under the name
353	C<$name>. If the name already exists it is replaced.
354
355	A port can only be registered under one well known name.
356
357	A port automatically becomes unregistered when it is killed.
358
359	=cut
360
361	sub reg(@) {
362	my $port = @_ > 1 ? shift : $SELF \|\| Carp::croak 'reg: called with one argument only, but $SELF not set,';
363
364	$REG{$_[0]} = $port;
365	}
366
367	=item rcv $port, $callback->(@msg)	330	=item rcv $local_port, $callback->(@msg)
368		331
369	Replaces the callback on the specified miniport (after converting it to	332	Replaces the default callback on the specified port. There is no way to
370	one if required).	333	remove the default callback: use C<sub { }> to disable it, or better
371		334	C<kil> the port when it is no longer needed.
372	=item rcv $port, tagstring => $callback->(@msg), ...
373
374	=item rcv $port, $smartmatch => $callback->(@msg), ...
375
376	=item rcv $port, [$smartmatch...] => $callback->(@msg), ...
377
378	Register callbacks to be called on matching messages on the given full
379	port (after converting it to one if required) and return the port.
380
381	The callback has to return a true value when its work is done, after
382	which is will be removed, or a false value in which case it will stay
383	registered.
384		335
385	The global C<$SELF> (exported by this module) contains C<$port> while	336	The global C<$SELF> (exported by this module) contains C<$port> while
386	executing the callback.	337	executing the callback. Runtime errors during callback execution will
		338	result in the port being C<kil>ed.
387		339
388	Runtime errors during callback execution will result in the port being	340	The default callback received all messages not matched by a more specific
389	C<kil>ed.	341	C<tag> match.
390		342
391	If the match is an array reference, then it will be matched against the	343	=item rcv $local_port, tag => $callback->(@msg_without_tag), ...
392	first elements of the message, otherwise only the first element is being
393	matched.
394		344
395	Any element in the match that is specified as C<_any_> (a function	345	Register (or replace) callbacks to be called on messages starting with the
396	exported by this module) matches any single element of the message.	346	given tag on the given port (and return the port), or unregister it (when
		347	C<$callback> is C<$undef> or missing). There can only be one callback
		348	registered for each tag.
397		349
398	While not required, it is highly recommended that the first matching	350	The original message will be passed to the callback, after the first
399	element is a string identifying the message. The one-string-only match is	351	element (the tag) has been removed. The callback will use the same
400	also the most efficient match (by far).	352	environment as the default callback (see above).
401		353
402	Example: create a port and bind receivers on it in one go.	354	Example: create a port and bind receivers on it in one go.
403		355
404	my $port = rcv port,	356	my $port = rcv port,
405	msg1 => sub { ...; 0 },	357	msg1 => sub { ... },
406	msg2 => sub { ...; 0 },	358	msg2 => sub { ... },
407	;	359	;
408		360
409	Example: create a port, bind receivers and send it in a message elsewhere	361	Example: create a port, bind receivers and send it in a message elsewhere
410	in one go:	362	in one go:
411		363
412	snd $otherport, reply =>	364	snd $otherport, reply =>
413	rcv port,	365	rcv port,
414	msg1 => sub { ...; 0 },	366	msg1 => sub { ... },
415	...	367	...
416	;	368	;
		369
		370	Example: temporarily register a rcv callback for a tag matching some port
		371	(e.g. for a rpc reply) and unregister it after a message was received.
		372
		373	rcv $port, $otherport => sub {
		374	my @reply = @_;
		375
		376	rcv $SELF, $otherport;
		377	};
417		378
418	=cut	379	=cut
419		380
420	sub rcv($@) {	381	sub rcv($@) {
421	my $port = shift;	382	my $port = shift;
422	my ($noderef, $portid) = split /#/, $port, 2;	383	my ($noderef, $portid) = split /#/, $port, 2;
423		384
424	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}	385	$NODE{$noderef} == $NODE{""}
425	or Carp::croak "$port: rcv can only be called on local ports, caught";	386	or Carp::croak "$port: rcv can only be called on local ports, caught";
426		387
427	if (@_ == 1) {	388	while (@_) {
		389	if (ref $_[0]) {
		390	if (my $self = $PORT_DATA{$portid}) {
		391	"AnyEvent::MP::Port" eq ref $self
		392	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
		393
		394	$self->[2] = shift;
		395	} else {
428	my $cb = shift;	396	my $cb = shift;
429	delete $PORT_DATA{$portid};
430	$PORT{$portid} = sub {	397	$PORT{$portid} = sub {
431	local $SELF = $port;	398	local $SELF = $port;
432	eval {	399	eval { &$cb }; _self_die if $@;
433	&$cb	400	};
434	and kil $port;
435	};	401	}
436	_self_die if $@;	402	} elsif (defined $_[0]) {
437	};
438	} else {
439	my $self = $PORT_DATA{$portid} \|\|= do {	403	my $self = $PORT_DATA{$portid} \|\|= do {
440	my $self = bless {	404	my $self = bless [$PORT{$port} \|\| sub { }, { }, $port], "AnyEvent::MP::Port";
441	id => $port,
442	}, "AnyEvent::MP::Port";
443		405
444	$PORT{$portid} = sub {	406	$PORT{$portid} = sub {
445	local $SELF = $port;	407	local $SELF = $port;
446		408
447	eval {
448	for (@{ $self->{rc0}{$_[0]} }) {	409	if (my $cb = $self->[1]{$_[0]}) {
449	$_ && &{$_->[0]}	410	shift;
450	&& undef $_;	411	eval { &$cb }; _self_die if $@;
451	}	412	} else {
452
453	for (@{ $self->{rcv}{$_[0]} }) {
454	$_ && [@_[1 .. @{$_->[1]}]] ~~ $_->[1]
455	&& &{$_->[0]}	413	&{ $self->[0] };
456	&& undef $_;
457	}
458
459	for (@{ $self->{any} }) {
460	$_ && [@_[0 .. $#{$_->[1]}]] ~~ $_->[1]
461	&& &{$_->[0]}
462	&& undef $_;
463	}	414	}
464	};	415	};
465	_self_die if $@;	416
		417	$self
466	};	418	};
467		419
468	$self
469	};
470
471	"AnyEvent::MP::Port" eq ref $self	420	"AnyEvent::MP::Port" eq ref $self
472	or Carp::croak "$port: rcv can only be called on message matching ports, caught";	421	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
473		422
474	while (@_) {
475	my ($match, $cb) = splice @_, 0, 2;	423	my ($tag, $cb) = splice @_, 0, 2;
476		424
477	if (!ref $match) {	425	if (defined $cb) {
478	push @{ $self->{rc0}{$match} }, [$cb];	426	$self->[1]{$tag} = $cb;
479	} elsif (("ARRAY" eq ref $match && !ref $match->[0])) {
480	my ($type, @match) = @$match;
481	@match
482	? push @{ $self->{rcv}{$match->[0]} }, [$cb, \@match]
483	: push @{ $self->{rc0}{$match->[0]} }, [$cb];
484	} else {	427	} else {
485	push @{ $self->{any} }, [$cb, $match];	428	delete $self->[1]{$tag};
486	}	429	}
487	}	430	}
488	}	431	}
489		432
490	$port	433	$port
…		…
545	will arrive, or the monitoring action will be invoked after possible	488	will arrive, or the monitoring action will be invoked after possible
546	message loss has been detected. No messages will be lost "in between"	489	message loss has been detected. No messages will be lost "in between"
547	(after the first lost message no further messages will be received by the	490	(after the first lost message no further messages will be received by the
548	port). After the monitoring action was invoked, further messages might get	491	port). After the monitoring action was invoked, further messages might get
549	delivered again.	492	delivered again.
		493
		494	Note that monitoring-actions are one-shot: once released, they are removed
		495	and will not trigger again.
550		496
551	In the first form (callback), the callback is simply called with any	497	In the first form (callback), the callback is simply called with any
552	number of C<@reason> elements (no @reason means that the port was deleted	498	number of C<@reason> elements (no @reason means that the port was deleted
553	"normally"). Note also that I<< the callback B<must> never die >>, so use	499	"normally"). Note also that I<< the callback B<must> never die >>, so use
554	C<eval> if unsure.	500	C<eval> if unsure.
…		…
715	my $id = "$RUNIQ." . $ID++;	661	my $id = "$RUNIQ." . $ID++;
716		662
717	$_[0] =~ /::/	663	$_[0] =~ /::/
718	or Carp::croak "spawn init function must be a fully-qualified name, caught";	664	or Carp::croak "spawn init function must be a fully-qualified name, caught";
719		665
720	($NODE{$noderef} \|\| add_node $noderef)	666	snd_to_func $noderef, "AnyEvent::MP::_spawn" => $id, @_;
721	->send (["", "AnyEvent::MP::_spawn" => $id, @_]);
722		667
723	"$noderef#$id"	668	"$noderef#$id"
724	}	669	}
725		670
726	=back	671	=item after $timeout, @msg
727		672
728	=head1 NODE MESSAGES	673	=item after $timeout, $callback
729		674
730	Nodes understand the following messages sent to them. Many of them take	675	Either sends the given message, or call the given callback, after the
731	arguments called C<@reply>, which will simply be used to compose a reply	676	specified number of seconds.
732	message - C<$reply[0]> is the port to reply to, C<$reply[1]> the type and
733	the remaining arguments are simply the message data.
734		677
735	While other messages exist, they are not public and subject to change.	678	This is simply a utility function that come sin handy at times.
736		679
737	=over 4
738
739	=cut	680	=cut
740		681
741	=item lookup => $name, @reply	682	sub after($@) {
		683	my ($timeout, @action) = @_;
742		684
743	Replies with the port ID of the specified well-known port, or C<undef>.	685	my $t; $t = AE::timer $timeout, 0, sub {
744		686	undef $t;
745	=item devnull => ...	687	ref $action[0]
746		688	? $action[0]()
747	Generic data sink/CPU heat conversion.	689	: snd @action;
748		690	};
749	=item relay => $port, @msg	691	}
750
751	Simply forwards the message to the given port.
752
753	=item eval => $string[ @reply]
754
755	Evaluates the given string. If C<@reply> is given, then a message of the
756	form C<@reply, $@, @evalres> is sent.
757
758	Example: crash another node.
759
760	snd $othernode, eval => "exit";
761
762	=item time => @reply
763
764	Replies the the current node time to C<@reply>.
765
766	Example: tell the current node to send the current time to C<$myport> in a
767	C<timereply> message.
768
769	snd $NODE, time => $myport, timereply => 1, 2;
770	# => snd $myport, timereply => 1, 2, <time>
771		692
772	=back	693	=back
773		694
774	=head1 AnyEvent::MP vs. Distributed Erlang	695	=head1 AnyEvent::MP vs. Distributed Erlang
775		696
…		…
794	convenience functionality.	715	convenience functionality.
795		716
796	This means that AEMP requires a less tightly controlled environment at the	717	This means that AEMP requires a less tightly controlled environment at the
797	cost of longer node references and a slightly higher management overhead.	718	cost of longer node references and a slightly higher management overhead.
798		719
		720	=item * Erlang has a "remote ports are like local ports" philosophy, AEMP
		721	uses "local ports are like remote ports".
		722
		723	The failure modes for local ports are quite different (runtime errors
		724	only) then for remote ports - when a local port dies, you I<know> it dies,
		725	when a connection to another node dies, you know nothing about the other
		726	port.
		727
		728	Erlang pretends remote ports are as reliable as local ports, even when
		729	they are not.
		730
		731	AEMP encourages a "treat remote ports differently" philosophy, with local
		732	ports being the special case/exception, where transport errors cannot
		733	occur.
		734
799	=item * Erlang uses processes and a mailbox, AEMP does not queue.	735	=item * Erlang uses processes and a mailbox, AEMP does not queue.
800		736
801	Erlang uses processes that selctively receive messages, and therefore	737	Erlang uses processes that selectively receive messages, and therefore
802	needs a queue. AEMP is event based, queuing messages would serve no useful	738	needs a queue. AEMP is event based, queuing messages would serve no
803	purpose.	739	useful purpose. For the same reason the pattern-matching abilities of
		740	AnyEvent::MP are more limited, as there is little need to be able to
		741	filter messages without dequeing them.
804		742
805	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).	743	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).
806		744
807	=item * Erlang sends are synchronous, AEMP sends are asynchronous.	745	=item * Erlang sends are synchronous, AEMP sends are asynchronous.
808		746
809	Sending messages in Erlang is synchronous and blocks the process. AEMP	747	Sending messages in Erlang is synchronous and blocks the process (and
810	sends are immediate, connection establishment is handled in the	748	so does not need a queue that can overflow). AEMP sends are immediate,
811	background.	749	connection establishment is handled in the background.
812		750
813	=item * Erlang can silently lose messages, AEMP cannot.	751	=item * Erlang suffers from silent message loss, AEMP does not.
814		752
815	Erlang makes few guarantees on messages delivery - messages can get lost	753	Erlang makes few guarantees on messages delivery - messages can get lost
816	without any of the processes realising it (i.e. you send messages a, b,	754	without any of the processes realising it (i.e. you send messages a, b,
817	and c, and the other side only receives messages a and c).	755	and c, and the other side only receives messages a and c).
818		756
…		…
830	eventually be killed - it cannot happen that a node detects a port as dead	768	eventually be killed - it cannot happen that a node detects a port as dead
831	and then later sends messages to it, finding it is still alive.	769	and then later sends messages to it, finding it is still alive.
832		770
833	=item * Erlang can send messages to the wrong port, AEMP does not.	771	=item * Erlang can send messages to the wrong port, AEMP does not.
834		772
835	In Erlang it is quite possible that a node that restarts reuses a process	773	In Erlang it is quite likely that a node that restarts reuses a process ID
836	ID known to other nodes for a completely different process, causing	774	known to other nodes for a completely different process, causing messages
837	messages destined for that process to end up in an unrelated process.	775	destined for that process to end up in an unrelated process.
838		776
839	AEMP never reuses port IDs, so old messages or old port IDs floating	777	AEMP never reuses port IDs, so old messages or old port IDs floating
840	around in the network will not be sent to an unrelated port.	778	around in the network will not be sent to an unrelated port.
841		779
842	=item * Erlang uses unprotected connections, AEMP uses secure	780	=item * Erlang uses unprotected connections, AEMP uses secure

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Comparing cvsroot/AnyEvent-MP/MP.pm (file contents): Revision 1.49 by root, Thu Aug 13 15:29:58 2009 UTC vs. Revision 1.63 by root, Thu Aug 27 21:29:37 2009 UTC

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Comparing cvsroot/AnyEvent-MP/MP.pm (file contents):
Revision 1.49 by root, Thu Aug 13 15:29:58 2009 UTC vs.
Revision 1.63 by root, Thu Aug 27 21:29:37 2009 UTC