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

Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.49 by root, Thu Aug 13 15:29:58 2009 UTC vs.
Revision 1.52 by root, Fri Aug 14 15:13:20 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 $somple_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
…		…
148	kil $SELF, die => $msg;	143	kil $SELF, die => $msg;
149	}	144	}
150		145
151	=item $thisnode = NODE / $NODE	146	=item $thisnode = NODE / $NODE
152		147
153	The C<NODE> function returns, and the C<$NODE> variable contains	148	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	149	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	150	C<initialise_node>.
156	identifiers become invalid.
157		151
158	=item $noderef = node_of $port	152	=item $noderef = node_of $port
159		153
160	Extracts and returns the noderef from a portid or a noderef.	154	Extracts and returns the noderef from a port ID or a noderef.
161		155
162	=item initialise_node $noderef, $seednode, $seednode...	156	=item initialise_node $noderef, $seednode, $seednode...
163		157
164	=item initialise_node "slave/", $master, $master...	158	=item initialise_node "slave/", $master, $master...
165		159
…		…
284	=item snd $port, type => @data	278	=item snd $port, type => @data
285		279
286	=item snd $port, @msg	280	=item snd $port, @msg
287		281
288	Send the given message to the given port ID, which can identify either	282	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	283	a local or a remote port, and must be a port ID.
290	stringifies a sa port ID (such as a port object :).
291		284
292	While the message can be about anything, it is highly recommended to use a	285	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	286	string as first element (a port ID, or some word that indicates a request
294	type etc.).	287	type etc.).
295		288
296	The message data effectively becomes read-only after a call to this	289	The message data effectively becomes read-only after a call to this
297	function: modifying any argument is not allowed and can cause many	290	function: modifying any argument is not allowed and can cause many
298	problems.	291	problems.
…		…
303	that Storable can serialise and deserialise is allowed, and for the local	296	that Storable can serialise and deserialise is allowed, and for the local
304	node, anything can be passed.	297	node, anything can be passed.
305		298
306	=item $local_port = port	299	=item $local_port = port
307		300
308	Create a new local port object that can be used either as a pattern	301	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"),	302	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		303
312	=item $port = port { my @msg = @_; $finished }	304	=item $local_port = port { my @msg = @_ }
313		305
314	Creates a "miniport", that is, a very lightweight port without any pattern	306	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.	307	creating a port and calling C<rcv $port, $callback> on it.
317		308
318	The block will be called for every message received on the port. When the	309	The block will be called for every message received on the port, with the
319	callback returns a true value its job is considered "done" and the port	310	global variable C<$SELF> set to the port ID. Runtime errors will cause the
320	will be destroyed. Otherwise it will stay alive.	311	port to be C<kil>ed. The message will be passed as-is, no extra argument
		312	(i.e. no port ID) will be passed to the callback.
321		313
322	The message will be passed as-is, no extra argument (i.e. no port id) will	314	If you want to stop/destroy the port, simply C<kil> it:
323	be passed to the callback.
324		315
325	If you need the local port id in the callback, this works nicely:	316	my $port = port {
326		317	my @msg = @_;
327	my $port; $port = port {	318	...
328	snd $otherport, reply => $port;	319	kil $SELF;
329	};	320	};
330		321
331	=cut	322	=cut
332		323
333	sub rcv($@);	324	sub rcv($@);
		325
		326	sub _kilme {
		327	die "received message on port without callback";
		328	}
334		329
335	sub port(;&) {	330	sub port(;&) {
336	my $id = "$UNIQ." . $ID++;	331	my $id = "$UNIQ." . $ID++;
337	my $port = "$NODE#$id";	332	my $port = "$NODE#$id";
338		333
339	if (@_) {	334	rcv $port, shift \|\| \&_kilme;
340	rcv $port, shift;
341	} else {
342	$PORT{$id} = sub { }; # nop
343	}
344		335
345	$port	336	$port
346	}	337	}
347		338
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)	339	=item rcv $local_port, $callback->(@msg)
368		340
369	Replaces the callback on the specified miniport (after converting it to	341	Replaces the default callback on the specified port. There is no way to
370	one if required).	342	remove the default callback: use C<sub { }> to disable it, or better
371		343	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...] => $callback->(@msg), ...
377
378	Register callbacks to be called on matching messages on the given full
379	port (after converting it to one if required) and return the port.
380
381	The callback has to return a true value when its work is done, after
382	which is will be removed, or a false value in which case it will stay
383	registered.
384		344
385	The global C<$SELF> (exported by this module) contains C<$port> while	345	The global C<$SELF> (exported by this module) contains C<$port> while
386	executing the callback.	346	executing the callback. Runtime errors during callback execution will
		347	result in the port being C<kil>ed.
387		348
388	Runtime errors during callback execution will result in the port being	349	The default callback received all messages not matched by a more specific
389	C<kil>ed.	350	C<tag> match.
390		351
391	If the match is an array reference, then it will be matched against the	352	=item rcv $local_port, tag => $callback->(@msg_without_tag), ...
392	first elements of the message, otherwise only the first element is being
393	matched.
394		353
395	Any element in the match that is specified as C<_any_> (a function	354	Register callbacks to be called on messages starting with the given tag on
396	exported by this module) matches any single element of the message.	355	the given port (and return the port), or unregister it (when C<$callback>
		356	is C<$undef>).
397		357
398	While not required, it is highly recommended that the first matching	358	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	359	element (the tag) has been removed. The callback will use the same
400	also the most efficient match (by far).	360	environment as the default callback (see above).
401		361
402	Example: create a port and bind receivers on it in one go.	362	Example: create a port and bind receivers on it in one go.
403		363
404	my $port = rcv port,	364	my $port = rcv port,
405	msg1 => sub { ...; 0 },	365	msg1 => sub { ... },
406	msg2 => sub { ...; 0 },	366	msg2 => sub { ... },
407	;	367	;
408		368
409	Example: create a port, bind receivers and send it in a message elsewhere	369	Example: create a port, bind receivers and send it in a message elsewhere
410	in one go:	370	in one go:
411		371
412	snd $otherport, reply =>	372	snd $otherport, reply =>
413	rcv port,	373	rcv port,
414	msg1 => sub { ...; 0 },	374	msg1 => sub { ... },
415	...	375	...
416	;	376	;
417		377
418	=cut	378	=cut
419		379
…		…
422	my ($noderef, $portid) = split /#/, $port, 2;	382	my ($noderef, $portid) = split /#/, $port, 2;
423		383
424	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}	384	($NODE{$noderef} \|\| add_node $noderef) == $NODE{""}
425	or Carp::croak "$port: rcv can only be called on local ports, caught";	385	or Carp::croak "$port: rcv can only be called on local ports, caught";
426		386
427	if (@_ == 1) {	387	while (@_) {
		388	if (ref $_[0]) {
		389	if (my $self = $PORT_DATA{$portid}) {
		390	"AnyEvent::MP::Port" eq ref $self
		391	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
		392
		393	$self->[2] = shift;
		394	} else {
428	my $cb = shift;	395	my $cb = shift;
429	delete $PORT_DATA{$portid};
430	$PORT{$portid} = sub {	396	$PORT{$portid} = sub {
431	local $SELF = $port;	397	local $SELF = $port;
432	eval {	398	eval { &$cb }; _self_die if $@;
433	&$cb	399	};
434	and kil $port;
435	};	400	}
436	_self_die if $@;	401	} elsif (defined $_[0]) {
437	};
438	} else {
439	my $self = $PORT_DATA{$portid} \|\|= do {	402	my $self = $PORT_DATA{$portid} \|\|= do {
440	my $self = bless {	403	my $self = bless [$PORT{$port} \|\| sub { }, { }, $port], "AnyEvent::MP::Port";
441	id => $port,
442	}, "AnyEvent::MP::Port";
443		404
444	$PORT{$portid} = sub {	405	$PORT{$portid} = sub {
445	local $SELF = $port;	406	local $SELF = $port;
446		407
447	eval {
448	for (@{ $self->{rc0}{$_[0]} }) {	408	if (my $cb = $self->[1]{$_[0]}) {
449	$_ && &{$_->[0]}	409	shift;
450	&& undef $_;	410	eval { &$cb }; _self_die if $@;
451	}	411	} else {
452
453	for (@{ $self->{rcv}{$_[0]} }) {
454	$_ && [@_[1 .. @{$_->[1]}]] ~~ $_->[1]
455	&& &{$_->[0]}	412	&{ $self->[0] };
456	&& undef $_;
457	}
458
459	for (@{ $self->{any} }) {
460	$_ && [@_[0 .. $#{$_->[1]}]] ~~ $_->[1]
461	&& &{$_->[0]}
462	&& undef $_;
463	}	413	}
464	};	414	};
465	_self_die if $@;	415
		416	$self
466	};	417	};
467		418
468	$self
469	};
470
471	"AnyEvent::MP::Port" eq ref $self	419	"AnyEvent::MP::Port" eq ref $self
472	or Carp::croak "$port: rcv can only be called on message matching ports, caught";	420	or Carp::croak "$port: rcv can only be called on message matching ports, caught";
473		421
474	while (@_) {
475	my ($match, $cb) = splice @_, 0, 2;	422	my ($tag, $cb) = splice @_, 0, 2;
476		423
477	if (!ref $match) {	424	if (defined $cb) {
478	push @{ $self->{rc0}{$match} }, [$cb];	425	$self->[1]{$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 {	426	} else {
485	push @{ $self->{any} }, [$cb, $match];	427	delete $self->[1]{$tag};
486	}	428	}
487	}	429	}
488	}	430	}
489		431
490	$port	432	$port
…		…
794	convenience functionality.	736	convenience functionality.
795		737
796	This means that AEMP requires a less tightly controlled environment at the	738	This means that AEMP requires a less tightly controlled environment at the
797	cost of longer node references and a slightly higher management overhead.	739	cost of longer node references and a slightly higher management overhead.
798		740
		741	=item Erlang has a "remote ports are like local ports" philosophy, AEMP
		742	uses "local ports are like remote ports".
		743
		744	The failure modes for local ports are quite different (runtime errors
		745	only) then for remote ports - when a local port dies, you I<know> it dies,
		746	when a connection to another node dies, you know nothing about the other
		747	port.
		748
		749	Erlang pretends remote ports are as reliable as local ports, even when
		750	they are not.
		751
		752	AEMP encourages a "treat remote ports differently" philosophy, with local
		753	ports being the special case/exception, where transport errors cannot
		754	occur.
		755
799	=item * Erlang uses processes and a mailbox, AEMP does not queue.	756	=item * Erlang uses processes and a mailbox, AEMP does not queue.
800		757
801	Erlang uses processes that selctively receive messages, and therefore	758	Erlang uses processes that selectively receive messages, and therefore
802	needs a queue. AEMP is event based, queuing messages would serve no useful	759	needs a queue. AEMP is event based, queuing messages would serve no
803	purpose.	760	useful purpose. For the same reason the pattern-matching abilities of
		761	AnyEvent::MP are more limited, as there is little need to be able to
		762	filter messages without dequeing them.
804		763
805	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).	764	(But see L<Coro::MP> for a more Erlang-like process model on top of AEMP).
806		765
807	=item * Erlang sends are synchronous, AEMP sends are asynchronous.	766	=item * Erlang sends are synchronous, AEMP sends are asynchronous.
808		767
809	Sending messages in Erlang is synchronous and blocks the process. AEMP	768	Sending messages in Erlang is synchronous and blocks the process (and
810	sends are immediate, connection establishment is handled in the	769	so does not need a queue that can overflow). AEMP sends are immediate,
811	background.	770	connection establishment is handled in the background.
812		771
813	=item * Erlang can silently lose messages, AEMP cannot.	772	=item * Erlang suffers from silent message loss, AEMP does not.
814		773
815	Erlang makes few guarantees on messages delivery - messages can get lost	774	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,	775	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).	776	and c, and the other side only receives messages a and c).
818		777
…		…
830	eventually be killed - it cannot happen that a node detects a port as dead	789	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.	790	and then later sends messages to it, finding it is still alive.
832		791
833	=item * Erlang can send messages to the wrong port, AEMP does not.	792	=item * Erlang can send messages to the wrong port, AEMP does not.
834		793
835	In Erlang it is quite possible that a node that restarts reuses a process	794	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	795	known to other nodes for a completely different process, causing messages
837	messages destined for that process to end up in an unrelated process.	796	destined for that process to end up in an unrelated process.
838		797
839	AEMP never reuses port IDs, so old messages or old port IDs floating	798	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.	799	around in the network will not be sent to an unrelated port.
841		800
842	=item * Erlang uses unprotected connections, AEMP uses secure	801	=item * Erlang uses unprotected connections, AEMP uses secure

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Comparing AnyEvent-MP/MP.pm (file contents): Revision 1.49 by root, Thu Aug 13 15:29:58 2009 UTC vs. Revision 1.52 by root, Fri Aug 14 15:13:20 2009 UTC

Diff Legend

Comparing AnyEvent-MP/MP.pm (file contents):
Revision 1.49 by root, Thu Aug 13 15:29:58 2009 UTC vs.
Revision 1.52 by root, Fri Aug 14 15:13:20 2009 UTC