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);
183 =head2 mk_group_wo_accessors
185 __PACKAGE__->mk_group_wo_accessors(simple => 'lie', [ subject => 'subj' ]);
189 =item Arguments: $group, @fieldspec
195 Creates a set of write only accessors in a given group. Identical to
196 L</mk_group_accessors> but accessors will throw an error if not passed a
197 value rather than getting the value.
201 sub mk_group_wo_accessors {
202 my($self, $group, @fields) = @_;
204 $self->_mk_group_accessors('make_group_wo_accessor', $group, @fields);
211 =item Arguments: $field
217 Simple getter for hash-based objects which returns the value for the field
218 name passed as an argument.
223 return $_[0]->{$_[1]};
230 =item Arguments: $field, $new_value
236 Simple setter for hash-based objects which sets and then returns the value
237 for the field name passed as an argument.
242 return $_[0]->{$_[1]} = $_[2];
250 =item Arguments: $field
256 Simple getter for Classes and hash-based objects which returns the value for
257 the field name passed as an argument. This behaves much like
258 L<Class::Data::Accessor> where the field can be set in a base class,
259 inherited and changed in subclasses, and inherited and changed for object
267 if ( defined( $class = Scalar::Util::blessed $_[0] ) ) {
268 if (Scalar::Util::reftype $_[0] eq 'HASH') {
269 return $_[0]->{$_[1]} if exists $_[0]->{$_[1]};
272 Carp::croak('Cannot get inherited value on an object instance that is not hash-based');
280 no warnings 'uninitialized';
282 my $cag_slot = '::__cag_'. $_[1];
283 return ${$class.$cag_slot} if defined(${$class.$cag_slot});
285 do { return ${$_.$cag_slot} if defined(${$_.$cag_slot}) }
286 for $_[0]->get_super_paths;
295 =item Arguments: $field, $new_value
301 Simple setter for Classes and hash-based objects which sets and then returns
302 the value for the field name passed as an argument. When called on a hash-based
303 object it will set the appropriate hash key value. When called on a class, it
304 will set a class level variable.
306 B<Note:>: This method will die if you try to set an object variable on a non
312 if (defined Scalar::Util::blessed $_[0]) {
313 if (Scalar::Util::reftype $_[0] eq 'HASH') {
314 return $_[0]->{$_[1]} = $_[2];
316 Carp::croak('Cannot set inherited value on an object instance that is not hash-based');
321 return ${$_[0].'::__cag_'.$_[1]} = $_[2];
325 =head2 get_component_class
329 =item Arguments: $field
335 Gets the value of the specified component class.
337 __PACKAGE__->mk_group_accessors('component_class' => 'result_class');
339 $self->result_class->method();
342 $self->get_component_class('result_class')->method();
346 sub get_component_class {
347 return $_[0]->get_inherited($_[1]);
350 =head2 set_component_class
354 =item Arguments: $field, $class
360 Inherited accessor that automatically loads the specified class before setting
361 it. This method will die if the specified class could not be loaded.
363 __PACKAGE__->mk_group_accessors('component_class' => 'result_class');
364 __PACKAGE__->result_class('MyClass');
366 $self->result_class->method();
370 sub set_component_class {
371 if (defined $_[2] and length $_[2]) {
372 # disable warnings, and prevent $_ being eaten away by a behind-the-scenes
376 if (__CAG_ENV__::UNSTABLE_DOLLARAT) {
380 eval { Module::Runtime::use_package_optimistically($_[2]) }
383 Carp::croak("Could not load $_[1] '$_[2]': $err") if defined $err;
387 eval { Module::Runtime::use_package_optimistically($_[2]) }
388 or Carp::croak("Could not load $_[1] '$_[2]': $@");
392 return $_[0]->set_inherited($_[1], $_[2]);
395 =head1 INTERNAL METHODS
397 These methods are documented for clarity, but are never meant to be called
398 directly, and are not really meant for overriding either.
400 =head2 get_super_paths
402 Returns a list of 'parent' or 'super' class names that the current class
403 inherited from. This is what drives the traversal done by L</get_inherited>.
407 sub get_super_paths {
408 return @{mro::get_linear_isa( ref($_[0]) || $_[0] )};
411 =head2 make_group_accessor
413 __PACKAGE__->make_group_accessor('simple', 'hair_length', 'hair_length');
414 __PACKAGE__->make_group_accessor('simple', 'hc', 'hair_color');
418 =item Arguments: $group, $field, $accessor
420 Returns: \&accessor_coderef ?
424 Called by mk_group_accessors for each entry in @fieldspec. Either returns
425 a coderef which will be installed at C<&__PACKAGE__::$accessor>, or returns
426 C<undef> if it elects to install the coderef on its own.
430 sub make_group_accessor { $gen_accessor->('rw', @_) }
432 =head2 make_group_ro_accessor
434 __PACKAGE__->make_group_ro_accessor('simple', 'birthdate', 'birthdate');
435 __PACKAGE__->make_group_ro_accessor('simple', 'ssn', 'social_security_number');
439 =item Arguments: $group, $field, $accessor
441 Returns: \&accessor_coderef ?
445 Called by mk_group_ro_accessors for each entry in @fieldspec. Either returns
446 a coderef which will be installed at C<&__PACKAGE__::$accessor>, or returns
447 C<undef> if it elects to install the coderef on its own.
451 sub make_group_ro_accessor { $gen_accessor->('ro', @_) }
453 =head2 make_group_wo_accessor
455 __PACKAGE__->make_group_wo_accessor('simple', 'lie', 'lie');
456 __PACKAGE__->make_group_wo_accessor('simple', 'subj', 'subject');
460 =item Arguments: $group, $field, $accessor
462 Returns: \&accessor_coderef ?
466 Called by mk_group_wo_accessors for each entry in @fieldspec. Either returns
467 a coderef which will be installed at C<&__PACKAGE__::$accessor>, or returns
468 C<undef> if it elects to install the coderef on its own.
472 sub make_group_wo_accessor { $gen_accessor->('wo', @_) }
477 To provide total flexibility L<Class::Accessor::Grouped> calls methods
478 internally while performing get/set actions, which makes it noticeably
479 slower than similar modules. To compensate, this module will automatically
480 use the insanely fast L<Class::XSAccessor> to generate the C<simple>-group
481 accessors if this module is available on your system.
485 This is the result of a set/get/set loop benchmark on perl 5.12.1 with
486 thread support, showcasing most popular accessor builders: L<Moose>, L<Mouse>,
487 L<Moo>, L<CAF|Class::Accessor::Fast>, L<CAF_XS|Class::Accessor::Fast::XS>,
488 L<XSA|Class::XSAccessor>, and L<CAF_XSA|Class::XSAccessor::Compat>:
490 Rate CAG moOse CAF moUse moo HANDMADE CAF_XS moUse_XS moo_XS CAF_XSA XSA CAG_XS
491 CAG 169/s -- -21% -24% -32% -32% -34% -59% -63% -67% -67% -67% -67%
492 moOse 215/s 27% -- -3% -13% -13% -15% -48% -53% -58% -58% -58% -58%
493 CAF 222/s 31% 3% -- -10% -10% -13% -46% -52% -57% -57% -57% -57%
494 moUse 248/s 46% 15% 11% -- -0% -3% -40% -46% -52% -52% -52% -52%
495 moo 248/s 46% 15% 11% 0% -- -3% -40% -46% -52% -52% -52% -52%
496 HANDMADE 255/s 50% 18% 14% 3% 3% -- -38% -45% -50% -51% -51% -51%
497 CAF_XS 411/s 143% 91% 85% 66% 66% 61% -- -11% -20% -20% -21% -21%
498 moUse_XS 461/s 172% 114% 107% 86% 86% 81% 12% -- -10% -11% -11% -11%
499 moo_XS 514/s 204% 139% 131% 107% 107% 102% 25% 12% -- -0% -1% -1%
500 CAF_XSA 516/s 205% 140% 132% 108% 108% 103% 26% 12% 0% -- -0% -0%
501 XSA 519/s 206% 141% 133% 109% 109% 104% 26% 13% 1% 0% -- -0%
502 CAG_XS 519/s 206% 141% 133% 109% 109% 104% 26% 13% 1% 0% 0% --
504 Benchmark program is available in the root of the
505 L<repository|http://search.cpan.org/dist/Class-Accessor-Grouped/>:
507 =head2 Notes on Class::XSAccessor
509 You can force (or disable) the use of L<Class::XSAccessor> before creating a
510 particular C<simple> accessor by either manipulating the global variable
511 C<$Class::Accessor::Grouped::USE_XS> to true or false (preferably with
512 L<localization|perlfunc/local>, or you can do so before runtime via the
513 C<CAG_USE_XS> environment variable.
515 Since L<Class::XSAccessor> has no knowledge of L</get_simple> and
516 L</set_simple> this module does its best to detect if you are overriding
517 one of these methods and will fall back to using the perl version of the
518 accessor in order to maintain consistency. However be aware that if you
519 enable use of C<Class::XSAccessor> (automatically or explicitly), create
520 an object, invoke a simple accessor on that object, and B<then> manipulate
521 the symbol table to install a C<get/set_simple> override - you get to keep
526 Matt S. Trout <mst@shadowcatsystems.co.uk>
528 Christopher H. Laco <claco@chrislaco.com>
532 Caelum: Rafael Kitover <rkitover@cpan.org>
534 frew: Arthur Axel "fREW" Schmidt <frioux@gmail.com>
536 groditi: Guillermo Roditi <groditi@cpan.org>
538 Jason Plum <jason.plum@bmmsi.com>
540 ribasushi: Peter Rabbitson <ribasushi@cpan.org>
543 =head1 COPYRIGHT & LICENSE
545 Copyright (c) 2006-2010 Matt S. Trout <mst@shadowcatsystems.co.uk>
547 This program is free software; you can redistribute it and/or modify
548 it under the same terms as perl itself.
552 ########################################################################
553 ########################################################################
554 ########################################################################
556 # Here be many angry dragons
557 # (all code is in private coderefs since everything inherits CAG)
559 ########################################################################
560 ########################################################################
562 # Autodetect unless flag supplied
563 my $xsa_autodetected;
564 if (! defined $USE_XS) {
565 $USE_XS = __CAG_ENV__::NO_CXSA ? 0 : 1;
569 my $maker_templates = {
571 xs_call => 'accessors',
573 my $set = "set_$_[0]";
574 my $get = "get_$_[0]";
580 ? shift->$set('$field', \@_)
581 : shift->$get('$field')
586 xs_call => 'getters',
588 my $get = "get_$_[0]";
594 ? shift->$get('$field')
596 my \$caller = caller;
597 my \$class = ref \$_[0] || \$_[0];
598 Carp::croak(\"'\$caller' cannot alter the value of '$field' \".
599 \"(read-only attributes of class '\$class')\");
605 xs_call => 'setters',
607 my $set = "set_$_[0]";
613 ? shift->$set('$field', \@_)
615 my \$caller = caller;
616 my \$class = ref \$_[0] || \$_[0];
617 Carp::croak(\"'\$caller' cannot access the value of '$field' \".
618 \"(write-only attributes of class '\$class')\");
626 my ($accessor_maker_cache, $no_xsa_warned_classes);
628 # can't use pkg_gen to track this stuff, as it doesn't
629 # detect superclass mucking
630 my $original_simple_getter = __PACKAGE__->can ('get_simple');
631 my $original_simple_setter = __PACKAGE__->can ('set_simple');
633 # Note!!! Unusual signature
634 $gen_accessor = sub {
635 my ($type, $class, $group, $field, $methname) = @_;
636 if (my $c = Scalar::Util::blessed( $class )) {
640 # When installing an XSA simple accessor, we need to make sure we are not
641 # short-circuiting a (compile or runtime) get_simple/set_simple override.
642 # What we do here is install a lazy first-access check, which will decide
643 # the ultimate coderef being placed in the accessor slot
645 # Also note that the *original* class will always retain this shim, as
646 # different branches inheriting from it may have different overrides.
647 # Thus the final method (properly labeled and all) is installed in the
648 # calling-package's namespace
649 if ($USE_XS and $group eq 'simple') {
650 die sprintf( "Class::XSAccessor requested but not available:\n%s\n", __CAG_ENV__::NO_CXSA )
651 if __CAG_ENV__::NO_CXSA;
653 my ($expected_cref, $cached_implementation);
654 my $ret = $expected_cref = sub {
655 my $current_class = Scalar::Util::blessed( $_[0] ) || $_[0];
657 # $cached_implementation will be set only if the shim got
658 # 'around'ed, in which case it is handy to avoid re-running
659 # this block over and over again
660 my $resolved_implementation = $cached_implementation->{$current_class} || do {
662 ($current_class->can('get_simple')||0) == $original_simple_getter
664 ($current_class->can('set_simple')||0) == $original_simple_setter
666 # nothing has changed, might as well use the XS crefs
668 # note that by the time this code executes, we already have
669 # *objects* (since XSA works on 'simple' only by definition).
670 # If someone is mucking with the symbol table *after* there
671 # are some objects already - look! many, shiny pieces! :)
673 # The weird breeder thingy is because XSA does not have an
674 # interface returning *just* a coderef, without installing it
676 Class::XSAccessor->import(
678 class => '__CAG__XSA__BREEDER__',
679 $maker_templates->{$type}{xs_call} => {
683 __CAG__XSA__BREEDER__->can($methname);
686 if (! $xsa_autodetected and ! $no_xsa_warned_classes->{$current_class}++) {
687 # not using Carp since the line where this happens doesn't mean much
688 warn 'Explicitly requested use of Class::XSAccessor disabled for objects of class '
689 . "'$current_class' inheriting from '$class' due to an overriden get_simple and/or "
694 # that's faster than local
696 my $c = $gen_accessor->($type, $class, 'simple', $field, $methname);
703 # if after this shim was created someone wrapped it with an 'around',
704 # we can not blindly reinstall the method slot - we will destroy the
705 # wrapper. Silently chain execution further...
706 if ( !$expected_cref or $expected_cref != ($current_class->can($methname)||0) ) {
708 # there is no point in re-determining it on every subsequent call,
709 # just store for future reference
710 $cached_implementation->{$current_class} ||= $resolved_implementation;
712 # older perls segfault if the cref behind the goto throws
713 # http://rt.perl.org/rt3/Public/Bug/Display.html?id=35878
714 return $resolved_implementation->(@_) if __CAG_ENV__::BROKEN_GOTO;
716 goto $resolved_implementation;
719 if (__CAG_ENV__::TRACK_UNDEFER_FAIL) {
720 my $deferred_calls_seen = do {
722 \%{"${current_class}::__cag_deferred_xs_shim_invocations"}
724 my @cframe = caller(0);
725 if (my $already_seen = $deferred_calls_seen->{$cframe[3]}) {
727 "Deferred version of method $cframe[3] invoked more than once (originally "
728 . "invoked at $already_seen). This is a strong indication your code has "
729 . 'cached the original ->can derived method coderef, and is using it instead '
730 . 'of the proper method re-lookup, causing performance regressions'
734 $deferred_calls_seen->{$cframe[3]} = "$cframe[1] line $cframe[2]";
738 # install the resolved implementation into the code slot so we do not
739 # come here anymore (hopefully)
740 # since XSAccessor was available - so is Sub::Name
743 no warnings 'redefine';
745 my $fq_name = "${current_class}::${methname}";
746 *$fq_name = Sub::Name::subname($fq_name, $resolved_implementation);
748 # need to update what the shim expects too *in case* its
749 # ->can was cached for some moronic reason
750 $expected_cref = $resolved_implementation;
751 Scalar::Util::weaken($expected_cref);
754 # older perls segfault if the cref behind the goto throws
755 # http://rt.perl.org/rt3/Public/Bug/Display.html?id=35878
756 return $resolved_implementation->(@_) if __CAG_ENV__::BROKEN_GOTO;
758 goto $resolved_implementation;
761 Scalar::Util::weaken($expected_cref); # to break the self-reference
765 # no Sub::Name - just install the coderefs directly (compiling every time)
766 elsif (__CAG_ENV__::NO_SUBNAME) {
767 my $src = $accessor_maker_cache->{source}{$type}{$group}{$field} ||=
768 $maker_templates->{$type}{pp_code}->($group, $field);
770 no warnings 'redefine';
771 local $@ if __CAG_ENV__::UNSTABLE_DOLLARAT;
772 eval "sub ${class}::${methname} { $src }";
774 undef; # so that no further attempt will be made to install anything
777 # a coderef generator with a variable pad (returns a fresh cref on every invocation)
779 ($accessor_maker_cache->{pp}{$type}{$group}{$field} ||= do {
780 my $src = $accessor_maker_cache->{source}{$type}{$group}{$field} ||=
781 $maker_templates->{$type}{pp_code}->($group, $field);
783 local $@ if __CAG_ENV__::UNSTABLE_DOLLARAT;
784 eval "sub { my \$dummy; sub { \$dummy if 0; $src } }" or die $@;