1 package Attribute::Handlers;
10 my ($pkg, $ref, $type) = @_;
11 return $symcache{$pkg,$ref} if $symcache{$pkg,$ref};
14 foreach my $sym ( values %{$pkg."::"} ) {
15 return $symcache{$pkg,$ref} = \$sym
16 if *{$sym}{$type} && *{$sym}{$type} == $ref;
21 VAR => [qw[SCALAR ARRAY HASH]],
22 ANY => [qw[SCALAR ARRAY HASH CODE]],
23 "" => [qw[SCALAR ARRAY HASH CODE]],
24 SCALAR => [qw[SCALAR]],
33 my %sigil = (SCALAR=>'$', ARRAY=>'@', HASH=>'%');
41 my @global_phases = qw(BEGIN CHECK INIT END);
44 croak "Usage: use $_[0] autotie => {AttrName => TieClassName,...}";
47 my $qual_id = qr/^[_a-z]\w*(::[_a-z]\w*)*$/i;
51 return unless $class eq "Attribute::Handlers";
54 if ($cmd =~ /^autotie((?:ref)?)$/) {
55 my $tiedata = ($1 ? '$ref, ' : '') . '@$data';
57 _usage_AH_ $class unless ref($mapping) eq 'HASH';
58 while (my($attr, $tieclass) = each %$mapping) {
59 $tieclass =~ s/^([_a-z]\w*(::[_a-z]\w*)*)(.*)/$1/is;
61 _usage_AH_ $class unless $attr =~ $qual_id
62 && $tieclass =~ $qual_id
63 && eval "use base $tieclass; 1";
64 if ($tieclass->isa('Exporter')) {
65 local $Exporter::ExportLevel = 2;
66 $tieclass->import(eval $args);
68 $attr =~ s/__CALLER__/caller(1)/e;
69 $attr = caller()."::".$attr unless $attr =~ /::/;
71 sub $attr : ATTR(VAR) {
72 my (\$ref, \$data) = \@_[2,4];
73 my \$was_arrayref = ref \$data eq 'ARRAY';
74 \$data = [ \$data ] unless \$was_arrayref;
75 my \$type = ref(\$ref)||"value (".(\$ref||"<undef>").")";
76 (\$type eq 'SCALAR')? tie \$\$ref,'$tieclass',$tiedata
77 :(\$type eq 'ARRAY') ? tie \@\$ref,'$tieclass',$tiedata
78 :(\$type eq 'HASH') ? tie \%\$ref,'$tieclass',$tiedata
79 : die "Can't autotie a \$type\n"
81 } or die "Internal error: $@";
85 croak "Can't understand $_";
89 sub _resolve_lastattr {
90 return unless $lastattr{ref};
91 my $sym = findsym @lastattr{'pkg','ref'}
92 or die "Internal error: $lastattr{pkg} symbol went missing";
93 my $name = *{$sym}{NAME};
94 warn "Declaration of $name attribute in package $lastattr{pkg} may clash with future reserved word\n"
95 if $^W and $name !~ /[A-Z]/;
96 foreach ( @{$validtype{$lastattr{type}}} ) {
97 *{"$lastattr{pkg}::_ATTR_${_}_${name}"} = $lastattr{ref};
103 my ($class) = $AUTOLOAD =~ m/(.*)::/g;
104 $AUTOLOAD =~ m/_ATTR_(.*?)_(.*)/ or
105 croak "Can't locate class method '$AUTOLOAD' via package '$class'";
106 croak "Attribute handler '$2' doesn't handle $1 attributes";
111 my $builtin = qr/lvalue|method|locked|unique|shared/;
113 sub _gen_handler_AH_() {
116 my ($pkg, $ref, @attrs) = @_;
117 my (undef, $filename, $linenum) = caller 2;
119 my ($attr, $data) = /^([a-z_]\w*)(?:[(](.*)[)])?$/is or next;
120 if ($attr eq 'ATTR') {
122 $raw{$ref} = $data =~ s/\s*,?\s*RAWDATA\s*,?\s*//;
123 $phase{$ref}{BEGIN} = 1
124 if $data =~ s/\s*,?\s*(BEGIN)\s*,?\s*//;
125 $phase{$ref}{INIT} = 1
126 if $data =~ s/\s*,?\s*(INIT)\s*,?\s*//;
127 $phase{$ref}{END} = 1
128 if $data =~ s/\s*,?\s*(END)\s*,?\s*//;
129 $phase{$ref}{CHECK} = 1
130 if $data =~ s/\s*,?\s*(CHECK)\s*,?\s*//
131 || ! keys %{$phase{$ref}};
132 # Added for cleanup to not pollute next call.
134 croak "Can't have two ATTR specifiers on one subroutine"
136 croak "Bad attribute type: ATTR($data)"
137 unless $validtype{$data};
138 %lastattr=(pkg=>$pkg,ref=>$ref,type=>$data);
142 my $handler = $pkg->can("_ATTR_${type}_${attr}");
143 next unless $handler;
144 my $decl = [$pkg, $ref, $attr, $data,
145 $raw{$handler}, $phase{$handler}, $filename, $linenum];
146 foreach my $gphase (@global_phases) {
147 _apply_handler_AH_($decl,$gphase)
148 if $global_phases{$gphase} <= $global_phase;
150 if ($global_phase != 0) {
151 # if _gen_handler_AH_ is being called after
152 # CHECK it's for a lexical, so make sure
153 # it didn't want to run anything later
155 local $Carp::CarpLevel = 2;
156 carp "Won't be able to apply END handler"
157 if $phase{$handler}{END};
160 push @declarations, $decl
165 return grep {defined && !/$builtin/} @attrs;
169 *{"Attribute::Handlers::UNIVERSAL::MODIFY_${_}_ATTRIBUTES"} =
170 _gen_handler_AH_ foreach @{$validtype{ANY}};
171 push @UNIVERSAL::ISA, 'Attribute::Handlers::UNIVERSAL'
172 unless grep /^Attribute::Handlers::UNIVERSAL$/, @UNIVERSAL::ISA;
174 sub _apply_handler_AH_ {
175 my ($declaration, $phase) = @_;
176 my ($pkg, $ref, $attr, $data, $raw, $handlerphase, $filename, $linenum) = @$declaration;
177 return unless $handlerphase->{$phase};
178 # print STDERR "Handling $attr on $ref in $phase with [$data]\n";
180 my $handler = "_ATTR_${type}_${attr}";
181 my $sym = findsym($pkg, $ref);
182 $sym ||= $type eq 'CODE' ? 'ANON' : 'LEXICAL';
184 my $evaled = !$raw && eval("package $pkg; no warnings;
185 local \$SIG{__WARN__}=sub{die}; [$data]");
186 $data = ($evaled && $data =~ /^\s*\[/) ? [$evaled]
187 : ($evaled) ? $evaled
190 (ref $sym eq 'GLOB' ? *{$sym}{ref $ref}||$ref : $ref),
192 (@$data>1? $data : $data->[0]),
205 _apply_handler_AH_($_,'CHECK') foreach @declarations;
210 _apply_handler_AH_($_,'INIT') foreach @declarations
214 END { $global_phase++; _apply_handler_AH_($_,'END') foreach @declarations }
221 Attribute::Handlers - Simpler definition of attribute handlers
225 This document describes version 0.78 of Attribute::Handlers,
226 released October 5, 2002.
232 use Attribute::Handlers;
233 no warnings 'redefine';
236 sub Good : ATTR(SCALAR) {
237 my ($package, $symbol, $referent, $attr, $data) = @_;
239 # Invoked for any scalar variable with a :Good attribute,
240 # provided the variable was declared in MyClass (or
241 # a derived class) or typed to MyClass.
243 # Do whatever to $referent here (executed in CHECK phase).
247 sub Bad : ATTR(SCALAR) {
248 # Invoked for any scalar variable with a :Bad attribute,
249 # provided the variable was declared in MyClass (or
250 # a derived class) or typed to MyClass.
254 sub Good : ATTR(ARRAY) {
255 # Invoked for any array variable with a :Good attribute,
256 # provided the variable was declared in MyClass (or
257 # a derived class) or typed to MyClass.
261 sub Good : ATTR(HASH) {
262 # Invoked for any hash variable with a :Good attribute,
263 # provided the variable was declared in MyClass (or
264 # a derived class) or typed to MyClass.
268 sub Ugly : ATTR(CODE) {
269 # Invoked for any subroutine declared in MyClass (or a
270 # derived class) with an :Ugly attribute.
275 # Invoked for any scalar, array, hash, or subroutine
276 # with an :Omni attribute, provided the variable or
277 # subroutine was declared in MyClass (or a derived class)
278 # or the variable was typed to MyClass.
279 # Use ref($_[2]) to determine what kind of referent it was.
284 use Attribute::Handlers autotie => { Cycle => Tie::Cycle };
286 my $next : Cycle(['A'..'Z']);
291 This module, when inherited by a package, allows that package's class to
292 define attribute handler subroutines for specific attributes. Variables
293 and subroutines subsequently defined in that package, or in packages
294 derived from that package may be given attributes with the same names as
295 the attribute handler subroutines, which will then be called in one of
296 the compilation phases (i.e. in a C<BEGIN>, C<CHECK>, C<INIT>, or C<END>
297 block). (C<UNITCHECK> blocks don't correspond to a global compilation
298 phase, so they can't be specified here.)
300 To create a handler, define it as a subroutine with the same name as
301 the desired attribute, and declare the subroutine itself with the
302 attribute C<:ATTR>. For example:
305 use Attribute::Handlers;
308 my ($package, $symbol, $referent, $attr, $data, $phase, $filename, $linenum) = @_;
311 *{$symbol}{NAME}, " ",
312 "($referent) ", "was just declared ",
313 "and ascribed the ${attr} attribute ",
314 "with data ($data)\n",
316 "in file $filename at line $linenum\n";
319 This creates a handler for the attribute C<:Loud> in the class LoudDecl.
320 Thereafter, any subroutine declared with a C<:Loud> attribute in the class
327 causes the above handler to be invoked, and passed:
333 the name of the package into which it was declared;
337 a reference to the symbol table entry (typeglob) containing the subroutine;
341 a reference to the subroutine;
345 the name of the attribute;
349 any data associated with that attribute;
353 the name of the phase in which the handler is being invoked;
357 the filename in which the handler is being invoked;
361 the line number in this file.
365 Likewise, declaring any variables with the C<:Loud> attribute within the
374 will cause the handler to be called with a similar argument list (except,
375 of course, that C<$_[2]> will be a reference to the variable).
377 The package name argument will typically be the name of the class into
378 which the subroutine was declared, but it may also be the name of a derived
379 class (since handlers are inherited).
381 If a lexical variable is given an attribute, there is no symbol table to
382 which it belongs, so the symbol table argument (C<$_[1]>) is set to the
383 string C<'LEXICAL'> in that case. Likewise, ascribing an attribute to
384 an anonymous subroutine results in a symbol table argument of C<'ANON'>.
386 The data argument passes in the value (if any) associated with the
387 attribute. For example, if C<&foo> had been declared:
389 sub foo :Loud("turn it up to 11, man!") {...}
391 then the string C<"turn it up to 11, man!"> would be passed as the
394 Attribute::Handlers makes strenuous efforts to convert
395 the data argument (C<$_[4]>) to a useable form before passing it to
396 the handler (but see L<"Non-interpretive attribute handlers">).
397 For example, all of these:
399 sub foo :Loud(till=>ears=>are=>bleeding) {...}
400 sub foo :Loud(['till','ears','are','bleeding']) {...}
401 sub foo :Loud(qw/till ears are bleeding/) {...}
402 sub foo :Loud(qw/my, ears, are, bleeding/) {...}
403 sub foo :Loud(till,ears,are,bleeding) {...}
405 causes it to pass C<['till','ears','are','bleeding']> as the handler's
406 data argument. However, if the data can't be parsed as valid Perl, then
407 it is passed as an uninterpreted string. For example:
409 sub foo :Loud(my,ears,are,bleeding) {...}
410 sub foo :Loud(qw/my ears are bleeding) {...}
412 cause the strings C<'my,ears,are,bleeding'> and C<'qw/my ears are bleeding'>
413 respectively to be passed as the data argument.
415 If the attribute has only a single associated scalar data value, that value is
416 passed as a scalar. If multiple values are associated, they are passed as an
417 array reference. If no value is associated with the attribute, C<undef> is
421 =head2 Typed lexicals
423 Regardless of the package in which it is declared, if a lexical variable is
424 ascribed an attribute, the handler that is invoked is the one belonging to
425 the package to which it is typed. For example, the following declarations:
429 my LoudDecl $loudobj : Loud;
430 my LoudDecl @loudobjs : Loud;
431 my LoudDecl %loudobjex : Loud;
433 causes the LoudDecl::Loud handler to be invoked (even if OtherClass also
434 defines a handler for C<:Loud> attributes).
437 =head2 Type-specific attribute handlers
439 If an attribute handler is declared and the C<:ATTR> specifier is
440 given the name of a built-in type (C<SCALAR>, C<ARRAY>, C<HASH>, or C<CODE>),
441 the handler is only applied to declarations of that type. For example,
442 the following definition:
446 sub RealLoud :ATTR(SCALAR) { print "Yeeeeow!" }
448 creates an attribute handler that applies only to scalars:
454 my $metal : RealLoud; # invokes &LoudDecl::RealLoud
455 my @metal : RealLoud; # error: unknown attribute
456 my %metal : RealLoud; # error: unknown attribute
457 sub metal : RealLoud {...} # error: unknown attribute
459 You can, of course, declare separate handlers for these types as well
460 (but you'll need to specify C<no warnings 'redefine'> to do it quietly):
463 use Attribute::Handlers;
464 no warnings 'redefine';
466 sub RealLoud :ATTR(SCALAR) { print "Yeeeeow!" }
467 sub RealLoud :ATTR(ARRAY) { print "Urrrrrrrrrr!" }
468 sub RealLoud :ATTR(HASH) { print "Arrrrrgggghhhhhh!" }
469 sub RealLoud :ATTR(CODE) { croak "Real loud sub torpedoed" }
471 You can also explicitly indicate that a single handler is meant to be
472 used for all types of referents like so:
475 use Attribute::Handlers;
477 sub SeriousLoud :ATTR(ANY) { warn "Hearing loss imminent" }
479 (I.e. C<ATTR(ANY)> is a synonym for C<:ATTR>).
482 =head2 Non-interpretive attribute handlers
484 Occasionally the strenuous efforts Attribute::Handlers makes to convert
485 the data argument (C<$_[4]>) to a useable form before passing it to
486 the handler get in the way.
488 You can turn off that eagerness-to-help by declaring
489 an attribute handler with the keyword C<RAWDATA>. For example:
491 sub Raw : ATTR(RAWDATA) {...}
492 sub Nekkid : ATTR(SCALAR,RAWDATA) {...}
493 sub Au::Naturale : ATTR(RAWDATA,ANY) {...}
495 Then the handler makes absolutely no attempt to interpret the data it
496 receives and simply passes it as a string:
498 my $power : Raw(1..100); # handlers receives "1..100"
500 =head2 Phase-specific attribute handlers
502 By default, attribute handlers are called at the end of the compilation
503 phase (in a C<CHECK> block). This seems to be optimal in most cases because
504 most things that can be defined are defined by that point but nothing has
507 However, it is possible to set up attribute handlers that are called at
508 other points in the program's compilation or execution, by explicitly
509 stating the phase (or phases) in which you wish the attribute handler to
510 be called. For example:
512 sub Early :ATTR(SCALAR,BEGIN) {...}
513 sub Normal :ATTR(SCALAR,CHECK) {...}
514 sub Late :ATTR(SCALAR,INIT) {...}
515 sub Final :ATTR(SCALAR,END) {...}
516 sub Bookends :ATTR(SCALAR,BEGIN,END) {...}
518 As the last example indicates, a handler may be set up to be (re)called in
519 two or more phases. The phase name is passed as the handler's final argument.
521 Note that attribute handlers that are scheduled for the C<BEGIN> phase
522 are handled as soon as the attribute is detected (i.e. before any
523 subsequently defined C<BEGIN> blocks are executed).
526 =head2 Attributes as C<tie> interfaces
528 Attributes make an excellent and intuitive interface through which to tie
529 variables. For example:
531 use Attribute::Handlers;
534 sub UNIVERSAL::Cycle : ATTR(SCALAR) {
535 my ($package, $symbol, $referent, $attr, $data, $phase) = @_;
536 $data = [ $data ] unless ref $data eq 'ARRAY';
537 tie $$referent, 'Tie::Cycle', $data;
544 my $next : Cycle('A'..'Z'); # $next is now a tied variable
550 Note that, because the C<Cycle> attribute receives its arguments in the
551 C<$data> variable, if the attribute is given a list of arguments, C<$data>
552 will consist of a single array reference; otherwise, it will consist of the
553 single argument directly. Since Tie::Cycle requires its cycling values to
554 be passed as an array reference, this means that we need to wrap
555 non-array-reference arguments in an array constructor:
557 $data = [ $data ] unless ref $data eq 'ARRAY';
559 Typically, however, things are the other way around: the tieable class expects
560 its arguments as a flattened list, so the attribute looks like:
562 sub UNIVERSAL::Cycle : ATTR(SCALAR) {
563 my ($package, $symbol, $referent, $attr, $data, $phase) = @_;
564 my @data = ref $data eq 'ARRAY' ? @$data : $data;
565 tie $$referent, 'Tie::Whatever', @data;
569 This software pattern is so widely applicable that Attribute::Handlers
570 provides a way to automate it: specifying C<'autotie'> in the
571 C<use Attribute::Handlers> statement. So, the cycling example,
572 could also be written:
574 use Attribute::Handlers autotie => { Cycle => 'Tie::Cycle' };
580 my $next : Cycle(['A'..'Z']); # $next is now a tied variable
585 Note that we now have to pass the cycling values as an array reference,
586 since the C<autotie> mechanism passes C<tie> a list of arguments as a list
587 (as in the Tie::Whatever example), I<not> as an array reference (as in
588 the original Tie::Cycle example at the start of this section).
590 The argument after C<'autotie'> is a reference to a hash in which each key is
591 the name of an attribute to be created, and each value is the class to which
592 variables ascribed that attribute should be tied.
594 Note that there is no longer any need to import the Tie::Cycle module --
595 Attribute::Handlers takes care of that automagically. You can even pass
596 arguments to the module's C<import> subroutine, by appending them to the
597 class name. For example:
599 use Attribute::Handlers
600 autotie => { Dir => 'Tie::Dir qw(DIR_UNLINK)' };
602 If the attribute name is unqualified, the attribute is installed in the
603 current package. Otherwise it is installed in the qualifier's package:
607 use Attribute::Handlers autotie => {
608 Other::Good => Tie::SecureHash, # tie attr installed in Other::
609 Bad => Tie::Taxes, # tie attr installed in Here::
610 UNIVERSAL::Ugly => Software::Patent # tie attr installed everywhere
613 Autoties are most commonly used in the module to which they actually tie,
614 and need to export their attributes to any module that calls them. To
615 facilitate this, Attribute::Handlers recognizes a special "pseudo-class" --
616 C<__CALLER__>, which may be specified as the qualifier of an attribute:
618 package Tie::Me::Kangaroo:Down::Sport;
620 use Attribute::Handlers autotie => { '__CALLER__::Roo' => __PACKAGE__ };
622 This causes Attribute::Handlers to define the C<Roo> attribute in the package
623 that imports the Tie::Me::Kangaroo:Down::Sport module.
625 Note that it is important to quote the __CALLER__::Roo identifier because
626 a bug in perl 5.8 will refuse to parse it and cause an unknown error.
628 =head3 Passing the tied object to C<tie>
630 Occasionally it is important to pass a reference to the object being tied
631 to the TIESCALAR, TIEHASH, etc. that ties it.
633 The C<autotie> mechanism supports this too. The following code:
635 use Attribute::Handlers autotieref => { Selfish => Tie::Selfish };
636 my $var : Selfish(@args);
638 has the same effect as:
640 tie my $var, 'Tie::Selfish', @args;
642 But when C<"autotieref"> is used instead of C<"autotie">:
644 use Attribute::Handlers autotieref => { Selfish => Tie::Selfish };
645 my $var : Selfish(@args);
647 the effect is to pass the C<tie> call an extra reference to the variable
650 tie my $var, 'Tie::Selfish', \$var, @args;
656 If the class shown in L<SYNOPSIS> were placed in the MyClass.pm
657 module, then the following code:
662 my MyClass $slr :Good :Bad(1**1-1) :Omni(-vorous);
664 package SomeOtherClass;
669 sub fn :Ugly(sister) :Omni('po',tent()) {...}
670 my @arr :Good :Omni(s/cie/nt/);
671 my %hsh :Good(q/bye) :Omni(q/bus/);
674 would cause the following handlers to be invoked:
676 # my MyClass $slr :Good :Bad(1**1-1) :Omni(-vorous);
678 MyClass::Good:ATTR(SCALAR)( 'MyClass', # class
679 'LEXICAL', # no typeglob
683 'CHECK', # compiler phase
686 MyClass::Bad:ATTR(SCALAR)( 'MyClass', # class
687 'LEXICAL', # no typeglob
691 'CHECK', # compiler phase
694 MyClass::Omni:ATTR(SCALAR)( 'MyClass', # class
695 'LEXICAL', # no typeglob
698 '-vorous' # eval'd attr data
699 'CHECK', # compiler phase
703 # sub fn :Ugly(sister) :Omni('po',tent()) {...}
705 MyClass::UGLY:ATTR(CODE)( 'SomeOtherClass', # class
706 \*SomeOtherClass::fn, # typeglob
707 \&SomeOtherClass::fn, # referent
709 'sister' # eval'd attr data
710 'CHECK', # compiler phase
713 MyClass::Omni:ATTR(CODE)( 'SomeOtherClass', # class
714 \*SomeOtherClass::fn, # typeglob
715 \&SomeOtherClass::fn, # referent
717 ['po','acle'] # eval'd attr data
718 'CHECK', # compiler phase
722 # my @arr :Good :Omni(s/cie/nt/);
724 MyClass::Good:ATTR(ARRAY)( 'SomeOtherClass', # class
725 'LEXICAL', # no typeglob
729 'CHECK', # compiler phase
732 MyClass::Omni:ATTR(ARRAY)( 'SomeOtherClass', # class
733 'LEXICAL', # no typeglob
736 "" # eval'd attr data
737 'CHECK', # compiler phase
741 # my %hsh :Good(q/bye) :Omni(q/bus/);
743 MyClass::Good:ATTR(HASH)( 'SomeOtherClass', # class
744 'LEXICAL', # no typeglob
747 'q/bye' # raw attr data
748 'CHECK', # compiler phase
751 MyClass::Omni:ATTR(HASH)( 'SomeOtherClass', # class
752 'LEXICAL', # no typeglob
755 'bus' # eval'd attr data
756 'CHECK', # compiler phase
760 Installing handlers into UNIVERSAL, makes them...err..universal.
763 package Descriptions;
764 use Attribute::Handlers;
767 sub name { return $name{$_[2]}||*{$_[1]}{NAME} }
769 sub UNIVERSAL::Name :ATTR {
770 $name{$_[2]} = $_[4];
773 sub UNIVERSAL::Purpose :ATTR {
774 print STDERR "Purpose of ", &name, " is $_[4]\n";
777 sub UNIVERSAL::Unit :ATTR {
778 print STDERR &name, " measured in $_[4]\n";
785 my $capacity : Name(capacity)
786 : Purpose(to store max storage capacity for files)
792 sub foo : Purpose(to foo all data before barring it) { }
801 =item C<Bad attribute type: ATTR(%s)>
803 An attribute handler was specified with an C<:ATTR(I<ref_type>)>, but the
804 type of referent it was defined to handle wasn't one of the five permitted:
805 C<SCALAR>, C<ARRAY>, C<HASH>, C<CODE>, or C<ANY>.
807 =item C<Attribute handler %s doesn't handle %s attributes>
809 A handler for attributes of the specified name I<was> defined, but not
810 for the specified type of declaration. Typically encountered whe trying
811 to apply a C<VAR> attribute handler to a subroutine, or a C<SCALAR>
812 attribute handler to some other type of variable.
814 =item C<Declaration of %s attribute in package %s may clash with future reserved word>
816 A handler for an attributes with an all-lowercase name was declared. An
817 attribute with an all-lowercase name might have a meaning to Perl
818 itself some day, even though most don't yet. Use a mixed-case attribute
821 =item C<Can't have two ATTR specifiers on one subroutine>
823 You just can't, okay?
824 Instead, put all the specifications together with commas between them
825 in a single C<ATTR(I<specification>)>.
827 =item C<Can't autotie a %s>
829 You can only declare autoties for types C<"SCALAR">, C<"ARRAY">, and
830 C<"HASH">. They're the only things (apart from typeglobs -- which are
831 not declarable) that Perl can tie.
833 =item C<Internal error: %s symbol went missing>
835 Something is rotten in the state of the program. An attributed
836 subroutine ceased to exist between the point it was declared and the point
837 at which its attribute handler(s) would have been called.
839 =item C<Won't be able to apply END handler>
841 You have defined an END handler for an attribute that is being applied
842 to a lexical variable. Since the variable may not be available during END
849 Damian Conway (damian@conway.org)
853 There are undoubtedly serious bugs lurking somewhere in code this funky :-)
854 Bug reports and other feedback are most welcome.
858 Copyright (c) 2001, Damian Conway. All Rights Reserved.
859 This module is free software. It may be used, redistributed
860 and/or modified under the same terms as Perl itself.