1 package Class::Accessor::Grouped;
6 use Module::Runtime ();
9 # use M::R to work around the 5.8 require bugs
11 Module::Runtime::require_module('MRO::Compat');
18 our $VERSION = '0.10006';
19 $VERSION = eval $VERSION if $VERSION =~ /_/; # numify for warning-free dev releases
21 # when changing minimum version don't forget to adjust Makefile.PL as well
22 our $__minimum_xsa_version;
23 BEGIN { $__minimum_xsa_version = '1.13' }
26 # the unless defined is here so that we can override the value
27 # before require/use, *regardless* of the state of $ENV{CAG_USE_XS}
28 $USE_XS = $ENV{CAG_USE_XS}
29 unless defined $USE_XS;
34 die "Huh?! No minimum C::XSA version?!\n"
35 unless $__minimum_xsa_version;
40 # individual (one const at a time) imports so we are 5.6.2 compatible
41 # if we can - why not ;)
42 constant->import( NO_SUBNAME => eval {
43 Module::Runtime::require_module('Sub::Name')
46 constant->import( NO_CXSA => ( !NO_SUBNAME() and eval {
47 Module::Runtime::use_module('Class::XSAccessor' => $__minimum_xsa_version)
50 constant->import( BROKEN_GOTO => ($] < '5.008009') ? 1 : 0 );
52 constant->import( UNSTABLE_DOLLARAT => ($] < '5.013002') ? 1 : 0 );
54 constant->import( TRACK_UNDEFER_FAIL => (
55 $INC{'Test/Builder.pm'} || $INC{'Test/Builder2.pm'}
57 $0 =~ m|^ x?t / .+ \.t $|x
61 # Yes this method is undocumented
62 # Yes it should be a private coderef like all the rest at the end of this file
63 # No we can't do that (yet) because the DBIC-CDBI compat layer overrides it
65 sub _mk_group_accessors {
66 my($self, $maker, $group, @fields) = @_;
67 my $class = Scalar::Util::blessed $self || $self;
70 no warnings 'redefine';
72 # So we don't have to do lots of lookups inside the loop.
73 $maker = $self->can($maker) unless ref $maker;
77 my ($name, $field) = (ref $_) ? (@$_) : ($_, $_);
79 for (qw/DESTROY AUTOLOAD CLONE/) {
80 Carp::carp("Having a data accessor named '$name' in '$class' is unwise.")
84 my $alias = "_${name}_accessor";
86 for my $meth ($name, $alias) {
88 # the maker may elect to not return anything, meaning it already
89 # installed the coderef for us (e.g. lack of Sub::Name)
90 my $cref = $self->$maker($group, $field, $meth)
93 my $fq_meth = "${class}::${meth}";
95 *$fq_meth = Sub::Name::subname($fq_meth, $cref);
96 #unless defined &{$class."\:\:$field"}
101 # coderef is setup at the end for clarity
106 Class::Accessor::Grouped - Lets you build groups of accessors
110 use base 'Class::Accessor::Grouped';
112 # make basic accessors for objects
113 __PACKAGE__->mk_group_accessors(simple => qw(id name email));
115 # make accessor that works for objects and classes
116 __PACKAGE__->mk_group_accessors(inherited => 'awesome_level');
120 This class lets you build groups of accessors that will call different
125 =head2 mk_group_accessors
127 __PACKAGE__->mk_group_accessors(simple => 'hair_length', [ hair_color => 'hc' ]);
131 =item Arguments: $group, @fieldspec
137 Creates a set of accessors in a given group.
139 $group is the name of the accessor group for the generated accessors; they
140 will call get_$group($field) on get and set_$group($field, $value) on set.
142 If you want to mimic Class::Accessor's mk_accessors $group has to be 'simple'
143 to tell Class::Accessor::Grouped to use its own get_simple and set_simple
146 @fieldspec is a list of field/accessor names; if a fieldspec is a scalar
147 this is used as both field and accessor name, if a listref it is expected to
148 be of the form [ $accessor, $field ].
152 sub mk_group_accessors {
153 my ($self, $group, @fields) = @_;
155 $self->_mk_group_accessors('make_group_accessor', $group, @fields);
159 =head2 mk_group_ro_accessors
161 __PACKAGE__->mk_group_ro_accessors(simple => 'birthdate', [ social_security_number => 'ssn' ]);
165 =item Arguments: $group, @fieldspec
171 Creates a set of read only accessors in a given group. Identical to
172 L</mk_group_accessors> but accessors will throw an error if passed a value
173 rather than setting the value.
177 sub mk_group_ro_accessors {
178 my($self, $group, @fields) = @_;
180 $self->_mk_group_accessors('make_group_ro_accessor', $group, @fields);
184 =head2 mk_group_wo_accessors
186 __PACKAGE__->mk_group_wo_accessors(simple => 'lie', [ subject => 'subj' ]);
190 =item Arguments: $group, @fieldspec
196 Creates a set of write only accessors in a given group. Identical to
197 L</mk_group_accessors> but accessors will throw an error if not passed a
198 value rather than getting the value.
202 sub mk_group_wo_accessors {
203 my($self, $group, @fields) = @_;
205 $self->_mk_group_accessors('make_group_wo_accessor', $group, @fields);
213 =item Arguments: $field
219 Simple getter for hash-based objects which returns the value for the field
220 name passed as an argument.
225 return $_[0]->{$_[1]};
232 =item Arguments: $field, $new_value
238 Simple setter for hash-based objects which sets and then returns the value
239 for the field name passed as an argument.
244 return $_[0]->{$_[1]} = $_[2];
252 =item Arguments: $field
258 Simple getter for Classes and hash-based objects which returns the value for
259 the field name passed as an argument. This behaves much like
260 L<Class::Data::Accessor> where the field can be set in a base class,
261 inherited and changed in subclasses, and inherited and changed for object
269 if ( defined( $class = Scalar::Util::blessed $_[0] ) ) {
270 if (Scalar::Util::reftype $_[0] eq 'HASH') {
271 return $_[0]->{$_[1]} if exists $_[0]->{$_[1]};
274 Carp::croak('Cannot get inherited value on an object instance that is not hash-based');
282 no warnings 'uninitialized';
284 my $cag_slot = '::__cag_'. $_[1];
285 return ${$class.$cag_slot} if defined(${$class.$cag_slot});
287 do { return ${$_.$cag_slot} if defined(${$_.$cag_slot}) }
288 for $_[0]->get_super_paths;
297 =item Arguments: $field, $new_value
303 Simple setter for Classes and hash-based objects which sets and then returns
304 the value for the field name passed as an argument. When called on a hash-based
305 object it will set the appropriate hash key value. When called on a class, it
306 will set a class level variable.
308 B<Note:>: This method will die if you try to set an object variable on a non
314 if (defined Scalar::Util::blessed $_[0]) {
315 if (Scalar::Util::reftype $_[0] eq 'HASH') {
316 return $_[0]->{$_[1]} = $_[2];
318 Carp::croak('Cannot set inherited value on an object instance that is not hash-based');
323 return ${$_[0].'::__cag_'.$_[1]} = $_[2];
327 =head2 get_component_class
331 =item Arguments: $field
337 Gets the value of the specified component class.
339 __PACKAGE__->mk_group_accessors('component_class' => 'result_class');
341 $self->result_class->method();
344 $self->get_component_class('result_class')->method();
348 sub get_component_class {
349 return $_[0]->get_inherited($_[1]);
352 =head2 set_component_class
356 =item Arguments: $field, $class
362 Inherited accessor that automatically loads the specified class before setting
363 it. This method will die if the specified class could not be loaded.
365 __PACKAGE__->mk_group_accessors('component_class' => 'result_class');
366 __PACKAGE__->result_class('MyClass');
368 $self->result_class->method();
372 sub set_component_class {
373 if (defined $_[2] and length $_[2]) {
374 # disable warnings, and prevent $_ being eaten away by a behind-the-scenes
378 if (__CAG_ENV__::UNSTABLE_DOLLARAT) {
382 eval { Module::Runtime::use_package_optimistically($_[2]) }
385 Carp::croak("Could not load $_[1] '$_[2]': $err") if defined $err;
389 eval { Module::Runtime::use_package_optimistically($_[2]) }
390 or Carp::croak("Could not load $_[1] '$_[2]': $@");
394 return $_[0]->set_inherited($_[1], $_[2]);
397 =head1 INTERNAL METHODS
399 These methods are documented for clarity, but are never meant to be called
400 directly, and are not really meant for overriding either.
402 =head2 get_super_paths
404 Returns a list of 'parent' or 'super' class names that the current class
405 inherited from. This is what drives the traversal done by L</get_inherited>.
409 sub get_super_paths {
410 # get_linear_isa returns the class itself as the 1st element
411 # use @_ as a pre-allocated scratch array
412 (undef, @_) = @{mro::get_linear_isa( length( ref($_[0]) ) ? ref($_[0]) : $_[0] )};
416 =head2 make_group_accessor
418 __PACKAGE__->make_group_accessor('simple', 'hair_length', 'hair_length');
419 __PACKAGE__->make_group_accessor('simple', 'hc', 'hair_color');
423 =item Arguments: $group, $field, $accessor
425 Returns: \&accessor_coderef ?
429 Called by mk_group_accessors for each entry in @fieldspec. Either returns
430 a coderef which will be installed at C<&__PACKAGE__::$accessor>, or returns
431 C<undef> if it elects to install the coderef on its own.
435 sub make_group_accessor { $gen_accessor->('rw', @_) }
437 =head2 make_group_ro_accessor
439 __PACKAGE__->make_group_ro_accessor('simple', 'birthdate', 'birthdate');
440 __PACKAGE__->make_group_ro_accessor('simple', 'ssn', 'social_security_number');
444 =item Arguments: $group, $field, $accessor
446 Returns: \&accessor_coderef ?
450 Called by mk_group_ro_accessors for each entry in @fieldspec. Either returns
451 a coderef which will be installed at C<&__PACKAGE__::$accessor>, or returns
452 C<undef> if it elects to install the coderef on its own.
456 sub make_group_ro_accessor { $gen_accessor->('ro', @_) }
458 =head2 make_group_wo_accessor
460 __PACKAGE__->make_group_wo_accessor('simple', 'lie', 'lie');
461 __PACKAGE__->make_group_wo_accessor('simple', 'subj', 'subject');
465 =item Arguments: $group, $field, $accessor
467 Returns: \&accessor_coderef ?
471 Called by mk_group_wo_accessors for each entry in @fieldspec. Either returns
472 a coderef which will be installed at C<&__PACKAGE__::$accessor>, or returns
473 C<undef> if it elects to install the coderef on its own.
477 sub make_group_wo_accessor { $gen_accessor->('wo', @_) }
482 To provide total flexibility L<Class::Accessor::Grouped> calls methods
483 internally while performing get/set actions, which makes it noticeably
484 slower than similar modules. To compensate, this module will automatically
485 use the insanely fast L<Class::XSAccessor> to generate the C<simple>-group
486 accessors if this module is available on your system.
490 This is the result of a set/get/set loop benchmark on perl 5.12.1 with
491 thread support, showcasing most popular accessor builders: L<Moose>, L<Mouse>,
492 L<Moo>, L<CAF|Class::Accessor::Fast>, L<CAF_XS|Class::Accessor::Fast::XS>,
493 L<XSA|Class::XSAccessor>, and L<CAF_XSA|Class::XSAccessor::Compat>:
495 Rate CAG moOse CAF moUse moo HANDMADE CAF_XS moUse_XS moo_XS CAF_XSA XSA CAG_XS
496 CAG 169/s -- -21% -24% -32% -32% -34% -59% -63% -67% -67% -67% -67%
497 moOse 215/s 27% -- -3% -13% -13% -15% -48% -53% -58% -58% -58% -58%
498 CAF 222/s 31% 3% -- -10% -10% -13% -46% -52% -57% -57% -57% -57%
499 moUse 248/s 46% 15% 11% -- -0% -3% -40% -46% -52% -52% -52% -52%
500 moo 248/s 46% 15% 11% 0% -- -3% -40% -46% -52% -52% -52% -52%
501 HANDMADE 255/s 50% 18% 14% 3% 3% -- -38% -45% -50% -51% -51% -51%
502 CAF_XS 411/s 143% 91% 85% 66% 66% 61% -- -11% -20% -20% -21% -21%
503 moUse_XS 461/s 172% 114% 107% 86% 86% 81% 12% -- -10% -11% -11% -11%
504 moo_XS 514/s 204% 139% 131% 107% 107% 102% 25% 12% -- -0% -1% -1%
505 CAF_XSA 516/s 205% 140% 132% 108% 108% 103% 26% 12% 0% -- -0% -0%
506 XSA 519/s 206% 141% 133% 109% 109% 104% 26% 13% 1% 0% -- -0%
507 CAG_XS 519/s 206% 141% 133% 109% 109% 104% 26% 13% 1% 0% 0% --
509 Benchmark program is available in the root of the
510 L<repository|http://search.cpan.org/dist/Class-Accessor-Grouped/>:
512 =head2 Notes on Class::XSAccessor
514 You can force (or disable) the use of L<Class::XSAccessor> before creating a
515 particular C<simple> accessor by either manipulating the global variable
516 C<$Class::Accessor::Grouped::USE_XS> to true or false (preferably with
517 L<localization|perlfunc/local>, or you can do so before runtime via the
518 C<CAG_USE_XS> environment variable.
520 Since L<Class::XSAccessor> has no knowledge of L</get_simple> and
521 L</set_simple> this module does its best to detect if you are overriding
522 one of these methods and will fall back to using the perl version of the
523 accessor in order to maintain consistency. However be aware that if you
524 enable use of C<Class::XSAccessor> (automatically or explicitly), create
525 an object, invoke a simple accessor on that object, and B<then> manipulate
526 the symbol table to install a C<get/set_simple> override - you get to keep
531 Matt S. Trout <mst@shadowcatsystems.co.uk>
533 Christopher H. Laco <claco@chrislaco.com>
537 Caelum: Rafael Kitover <rkitover@cpan.org>
539 frew: Arthur Axel "fREW" Schmidt <frioux@gmail.com>
541 groditi: Guillermo Roditi <groditi@cpan.org>
543 Jason Plum <jason.plum@bmmsi.com>
545 ribasushi: Peter Rabbitson <ribasushi@cpan.org>
548 =head1 COPYRIGHT & LICENSE
550 Copyright (c) 2006-2010 Matt S. Trout <mst@shadowcatsystems.co.uk>
552 This program is free software; you can redistribute it and/or modify
553 it under the same terms as perl itself.
557 ########################################################################
558 ########################################################################
559 ########################################################################
561 # Here be many angry dragons
562 # (all code is in private coderefs since everything inherits CAG)
564 ########################################################################
565 ########################################################################
567 # Autodetect unless flag supplied
568 my $xsa_autodetected;
569 if (! defined $USE_XS) {
570 $USE_XS = __CAG_ENV__::NO_CXSA ? 0 : 1;
574 my $maker_templates = {
576 xs_call => 'accessors',
578 my $set = "set_$_[0]";
579 my $get = "get_$_[0]";
585 ? shift->$set('$field', \@_)
586 : shift->$get('$field')
591 xs_call => 'getters',
593 my $get = "get_$_[0]";
599 ? shift->$get('$field')
601 my \$caller = caller;
602 my \$class = ref \$_[0] || \$_[0];
603 Carp::croak(\"'\$caller' cannot alter the value of '$field' \".
604 \"(read-only attributes of class '\$class')\");
610 xs_call => 'setters',
612 my $set = "set_$_[0]";
618 ? shift->$set('$field', \@_)
620 my \$caller = caller;
621 my \$class = ref \$_[0] || \$_[0];
622 Carp::croak(\"'\$caller' cannot access the value of '$field' \".
623 \"(write-only attributes of class '\$class')\");
631 my ($accessor_maker_cache, $no_xsa_warned_classes);
633 # can't use pkg_gen to track this stuff, as it doesn't
634 # detect superclass mucking
635 my $original_simple_getter = __PACKAGE__->can ('get_simple');
636 my $original_simple_setter = __PACKAGE__->can ('set_simple');
638 # Note!!! Unusual signature
639 $gen_accessor = sub {
640 my ($type, $class, $group, $field, $methname) = @_;
641 if (my $c = Scalar::Util::blessed( $class )) {
645 # When installing an XSA simple accessor, we need to make sure we are not
646 # short-circuiting a (compile or runtime) get_simple/set_simple override.
647 # What we do here is install a lazy first-access check, which will decide
648 # the ultimate coderef being placed in the accessor slot
650 # Also note that the *original* class will always retain this shim, as
651 # different branches inheriting from it may have different overrides.
652 # Thus the final method (properly labeled and all) is installed in the
653 # calling-package's namespace
654 if ($USE_XS and $group eq 'simple') {
655 die sprintf( "Class::XSAccessor requested but not available:\n%s\n", __CAG_ENV__::NO_CXSA )
656 if __CAG_ENV__::NO_CXSA;
658 my ($expected_cref, $cached_implementation);
659 my $ret = $expected_cref = sub {
660 my $current_class = Scalar::Util::blessed( $_[0] ) || $_[0];
662 # $cached_implementation will be set only if the shim got
663 # 'around'ed, in which case it is handy to avoid re-running
664 # this block over and over again
665 my $resolved_implementation = $cached_implementation->{$current_class} || do {
667 ($current_class->can('get_simple')||0) == $original_simple_getter
669 ($current_class->can('set_simple')||0) == $original_simple_setter
671 # nothing has changed, might as well use the XS crefs
673 # note that by the time this code executes, we already have
674 # *objects* (since XSA works on 'simple' only by definition).
675 # If someone is mucking with the symbol table *after* there
676 # are some objects already - look! many, shiny pieces! :)
678 # The weird breeder thingy is because XSA does not have an
679 # interface returning *just* a coderef, without installing it
681 Class::XSAccessor->import(
683 class => '__CAG__XSA__BREEDER__',
684 $maker_templates->{$type}{xs_call} => {
688 __CAG__XSA__BREEDER__->can($methname);
691 if (! $xsa_autodetected and ! $no_xsa_warned_classes->{$current_class}++) {
692 # not using Carp since the line where this happens doesn't mean much
693 warn 'Explicitly requested use of Class::XSAccessor disabled for objects of class '
694 . "'$current_class' inheriting from '$class' due to an overriden get_simple and/or "
699 # that's faster than local
701 my $c = $gen_accessor->($type, $class, 'simple', $field, $methname);
708 # if after this shim was created someone wrapped it with an 'around',
709 # we can not blindly reinstall the method slot - we will destroy the
710 # wrapper. Silently chain execution further...
711 if ( !$expected_cref or $expected_cref != ($current_class->can($methname)||0) ) {
713 # there is no point in re-determining it on every subsequent call,
714 # just store for future reference
715 $cached_implementation->{$current_class} ||= $resolved_implementation;
717 # older perls segfault if the cref behind the goto throws
718 # http://rt.perl.org/rt3/Public/Bug/Display.html?id=35878
719 return $resolved_implementation->(@_) if __CAG_ENV__::BROKEN_GOTO;
721 goto $resolved_implementation;
724 if (__CAG_ENV__::TRACK_UNDEFER_FAIL) {
725 my $deferred_calls_seen = do {
727 \%{"${current_class}::__cag_deferred_xs_shim_invocations"}
729 my @cframe = caller(0);
730 if (my $already_seen = $deferred_calls_seen->{$cframe[3]}) {
732 "Deferred version of method $cframe[3] invoked more than once (originally "
733 . "invoked at $already_seen). This is a strong indication your code has "
734 . 'cached the original ->can derived method coderef, and is using it instead '
735 . 'of the proper method re-lookup, causing performance regressions'
739 $deferred_calls_seen->{$cframe[3]} = "$cframe[1] line $cframe[2]";
743 # install the resolved implementation into the code slot so we do not
744 # come here anymore (hopefully)
745 # since XSAccessor was available - so is Sub::Name
748 no warnings 'redefine';
750 my $fq_name = "${current_class}::${methname}";
751 *$fq_name = Sub::Name::subname($fq_name, $resolved_implementation);
753 # need to update what the shim expects too *in case* its
754 # ->can was cached for some moronic reason
755 $expected_cref = $resolved_implementation;
756 Scalar::Util::weaken($expected_cref);
759 # older perls segfault if the cref behind the goto throws
760 # http://rt.perl.org/rt3/Public/Bug/Display.html?id=35878
761 return $resolved_implementation->(@_) if __CAG_ENV__::BROKEN_GOTO;
763 goto $resolved_implementation;
766 Scalar::Util::weaken($expected_cref); # to break the self-reference
770 # no Sub::Name - just install the coderefs directly (compiling every time)
771 elsif (__CAG_ENV__::NO_SUBNAME) {
772 my $src = $accessor_maker_cache->{source}{$type}{$group}{$field} ||=
773 $maker_templates->{$type}{pp_code}->($group, $field);
775 no warnings 'redefine';
776 local $@ if __CAG_ENV__::UNSTABLE_DOLLARAT;
777 eval "sub ${class}::${methname} { $src }";
779 undef; # so that no further attempt will be made to install anything
782 # a coderef generator with a variable pad (returns a fresh cref on every invocation)
784 ($accessor_maker_cache->{pp}{$type}{$group}{$field} ||= do {
785 my $src = $accessor_maker_cache->{source}{$type}{$group}{$field} ||=
786 $maker_templates->{$type}{pp_code}->($group, $field);
788 local $@ if __CAG_ENV__::UNSTABLE_DOLLARAT;
789 eval "sub { my \$dummy; sub { \$dummy if 0; $src } }" or die $@;