[gitmo/Package-Stash.git] / lib / Package / Stash / PP.pm

package Package::Stash::PP;
use strict;
use warnings;
# ABSTRACT: pure perl implementation of the Package::Stash API

use B;
use Carp qw(confess);
use Scalar::Util qw(blessed reftype weaken);
use Symbol;
# before 5.12, assigning to the ISA glob would make it lose its magical ->isa
# powers
use constant BROKEN_ISA_ASSIGNMENT => ($] < 5.012);
# before 5.10, stashes don't ever seem to drop to a refcount of zero, so
# weakening them isn't helpful
use constant BROKEN_WEAK_STASH     => ($] < 5.010);
# before 5.10, the scalar slot was always treated as existing if the
# glob existed
use constant BROKEN_SCALAR_INITIALIZATION => ($] < 5.010);
# add_method on anon stashes triggers rt.perl #1804 otherwise
# fixed in perl commit v5.13.3-70-g0fe688f
use constant BROKEN_GLOB_ASSIGNMENT => ($] < 5.013004);

=head1 SYNOPSIS

  use Package::Stash;

=head1 DESCRIPTION

This is a backend for L<Package::Stash> implemented in pure perl, for those without a compiler or who would like to use this inline in scripts.

=cut

sub new {
    my $class = shift;
    my ($package) = @_;

    if (!defined($package) || (ref($package) && reftype($package) ne 'HASH')) {
        confess "Package::Stash->new must be passed the name of the "
              . "package to access";
    }
    elsif (ref($package) && reftype($package) eq 'HASH') {
        confess "The PP implementation of Package::Stash does not support "
              . "anonymous stashes before perl 5.14"
            if BROKEN_GLOB_ASSIGNMENT;

        return bless {
            'namespace' => $package,
        }, $class;
    }
    elsif ($package =~ /\A[0-9A-Z_a-z]+(?:::[0-9A-Z_a-z]+)*\z/) {
        return bless {
            'package' => $package,
        }, $class;
    }
    else {
        confess "$package is not a module name";
    }

}

sub name {
    confess "Can't call name as a class method"
        unless blessed($_[0]);
    confess "Can't get the name of an anonymous package"
        unless defined($_[0]->{package});
    return $_[0]->{package};
}

sub namespace {
    confess "Can't call namespace as a class method"
        unless blessed($_[0]);

    if (BROKEN_WEAK_STASH) {
        no strict 'refs';
        return \%{$_[0]->name . '::'};
    }
    else {
        return $_[0]->{namespace} if defined $_[0]->{namespace};

        {
            no strict 'refs';
            $_[0]->{namespace} = \%{$_[0]->name . '::'};
        }

        weaken($_[0]->{namespace});

        return $_[0]->{namespace};
    }
}

{
    my %SIGIL_MAP = (
        '$' => 'SCALAR',
        '@' => 'ARRAY',
        '%' => 'HASH',
        '&' => 'CODE',
        ''  => 'IO',
    );

    sub _deconstruct_variable_name {
        my ($self, $variable) = @_;

        my @ret;
        if (ref($variable) eq 'HASH') {
            @ret = @{$variable}{qw[name sigil type]};
        }
        else {
            (defined $variable && length $variable)
                || confess "You must pass a variable name";

            my $sigil = substr($variable, 0, 1, '');

            if (exists $SIGIL_MAP{$sigil}) {
                @ret = ($variable, $sigil, $SIGIL_MAP{$sigil});
            }
            else {
                @ret = ("${sigil}${variable}", '', $SIGIL_MAP{''});
            }
        }

        # XXX in pure perl, this will access things in inner packages,
        # in xs, this will segfault - probably look more into this at
        # some point
        ($ret[0] !~ /::/)
            || confess "Variable names may not contain ::";

        return @ret;
    }
}

sub _valid_for_type {
    my $self = shift;
    my ($value, $type) = @_;
    if ($type eq 'HASH' || $type eq 'ARRAY'
     || $type eq 'IO'   || $type eq 'CODE') {
        return reftype($value) eq $type;
    }
    else {
        my $ref = reftype($value);
        return !defined($ref) || $ref eq 'SCALAR' || $ref eq 'REF' || $ref eq 'LVALUE' || $ref eq 'REGEXP' || $ref eq 'VSTRING';
    }
}

sub add_symbol {
    my ($self, $variable, $initial_value, %opts) = @_;

    my ($name, $sigil, $type) = $self->_deconstruct_variable_name($variable);

    if (@_ > 2) {
        $self->_valid_for_type($initial_value, $type)
            || confess "$initial_value is not of type $type";

        # cheap fail-fast check for PERLDBf_SUBLINE and '&'
        if ($^P and $^P & 0x10 && $sigil eq '&') {
            my $filename = $opts{filename};
            my $first_line_num = $opts{first_line_num};

            (undef, $filename, $first_line_num) = caller
                if not defined $filename;

            my $last_line_num = $opts{last_line_num} || ($first_line_num ||= 0);

            # http://perldoc.perl.org/perldebguts.html#Debugger-Internals
            $DB::sub{$self->name . '::' . $name} = "$filename:$first_line_num-$last_line_num";
        }
    }

    if (BROKEN_GLOB_ASSIGNMENT) {
        if (@_ > 2) {
            no strict 'refs';
            *{ $self->name . '::' . $name } = ref $initial_value
                ? $initial_value : \$initial_value;
        }
        else {
            no strict 'refs';
            *{ $self->name . '::' . $name };
        }
    }
    else {
        my $namespace = $self->namespace;
        $namespace->{$name} ||= *{ Symbol::gensym() };

        if (@_ > 2) {
            *{ $namespace->{$name} } = ref $initial_value
                ? $initial_value : \$initial_value;
        }
    }
}

sub remove_glob {
    my ($self, $name) = @_;
    delete $self->namespace->{$name};
}

sub has_symbol {
    my ($self, $variable) = @_;

    my ($name, $sigil, $type) = $self->_deconstruct_variable_name($variable);

    my $namespace = $self->namespace;

    return unless exists $namespace->{$name};

    my $entry_ref = \$namespace->{$name};
    if (reftype($entry_ref) eq 'GLOB') {
        if ($type eq 'SCALAR') {
            if (BROKEN_SCALAR_INITIALIZATION) {
                return defined ${ *{$entry_ref}{$type} };
            }
            else {
                return B::svref_2object($entry_ref)->SV->isa('B::SV');
            }
        }
        else {
            return defined *{$entry_ref}{$type};
        }
    }
    else {
        # a symbol table entry can be -1 (stub), string (stub with prototype),
        # or reference (constant)
        return $type eq 'CODE';
    }
}

sub get_symbol {
    my ($self, $variable, %opts) = @_;

    my ($name, $sigil, $type) = $self->_deconstruct_variable_name($variable);

    my $namespace = $self->namespace;

    if (!exists $namespace->{$name}) {
        if ($opts{vivify}) {
            if ($type eq 'ARRAY') {
                if (BROKEN_ISA_ASSIGNMENT) {
                    $self->add_symbol(
                        $variable,
                        $name eq 'ISA' ? () : ([])
                    );
                }
                else {
                    $self->add_symbol($variable, []);
                }
            }
            elsif ($type eq 'HASH') {
                $self->add_symbol($variable, {});
            }
            elsif ($type eq 'SCALAR') {
                $self->add_symbol($variable);
            }
            elsif ($type eq 'IO') {
                $self->add_symbol($variable, Symbol::geniosym);
            }
            elsif ($type eq 'CODE') {
                confess "Don't know how to vivify CODE variables";
            }
            else {
                confess "Unknown type $type in vivication";
            }
        }
        else {
            return undef;
        }
    }

    my $entry_ref = \$namespace->{$name};

    if (ref($entry_ref) eq 'GLOB') {
        return *{$entry_ref}{$type};
    }
    else {
        if ($type eq 'CODE') {
            # XXX we should really be able to support arbitrary anonymous
            # stashes here... (not just via Package::Anon)
            if (!BROKEN_GLOB_ASSIGNMENT
                && blessed($namespace)
                && $namespace->isa('Package::Anon')) {
                # ->can will call gv_init for us
                $namespace->bless(\(my $foo))->can($name);
                return *{ $namespace->{$name} }{CODE};
            }
            else {
                no strict 'refs';
                return \&{ $self->name . '::' . $name };
            }
        }
        else {
            return undef;
        }
    }
}

sub get_or_add_symbol {
    my $self = shift;
    $self->get_symbol(@_, vivify => 1);
}

sub remove_symbol {
    my ($self, $variable) = @_;

    my ($name, $sigil, $type) = $self->_deconstruct_variable_name($variable);

    # FIXME:
    # no doubt this is grossly inefficient and
    # could be done much easier and faster in XS

    my ($scalar_desc, $array_desc, $hash_desc, $code_desc, $io_desc) = (
        { sigil => '$', type => 'SCALAR', name => $name },
        { sigil => '@', type => 'ARRAY',  name => $name },
        { sigil => '%', type => 'HASH',   name => $name },
        { sigil => '&', type => 'CODE',   name => $name },
        { sigil => '',  type => 'IO',     name => $name },
    );

    my ($scalar, $array, $hash, $code, $io);
    if ($type eq 'SCALAR') {
        $array  = $self->get_symbol($array_desc)  if $self->has_symbol($array_desc);
        $hash   = $self->get_symbol($hash_desc)   if $self->has_symbol($hash_desc);
        $code   = $self->get_symbol($code_desc)   if $self->has_symbol($code_desc);
        $io     = $self->get_symbol($io_desc)     if $self->has_symbol($io_desc);
    }
    elsif ($type eq 'ARRAY') {
        $scalar = $self->get_symbol($scalar_desc) if $self->has_symbol($scalar_desc) || BROKEN_SCALAR_INITIALIZATION;
        $hash   = $self->get_symbol($hash_desc)   if $self->has_symbol($hash_desc);
        $code   = $self->get_symbol($code_desc)   if $self->has_symbol($code_desc);
        $io     = $self->get_symbol($io_desc)     if $self->has_symbol($io_desc);
    }
    elsif ($type eq 'HASH') {
        $scalar = $self->get_symbol($scalar_desc) if $self->has_symbol($scalar_desc) || BROKEN_SCALAR_INITIALIZATION;
        $array  = $self->get_symbol($array_desc)  if $self->has_symbol($array_desc);
        $code   = $self->get_symbol($code_desc)   if $self->has_symbol($code_desc);
        $io     = $self->get_symbol($io_desc)     if $self->has_symbol($io_desc);
    }
    elsif ($type eq 'CODE') {
        $scalar = $self->get_symbol($scalar_desc) if $self->has_symbol($scalar_desc) || BROKEN_SCALAR_INITIALIZATION;
        $array  = $self->get_symbol($array_desc)  if $self->has_symbol($array_desc);
        $hash   = $self->get_symbol($hash_desc)   if $self->has_symbol($hash_desc);
        $io     = $self->get_symbol($io_desc)     if $self->has_symbol($io_desc);
    }
    elsif ($type eq 'IO') {
        $scalar = $self->get_symbol($scalar_desc) if $self->has_symbol($scalar_desc) || BROKEN_SCALAR_INITIALIZATION;
        $array  = $self->get_symbol($array_desc)  if $self->has_symbol($array_desc);
        $hash   = $self->get_symbol($hash_desc)   if $self->has_symbol($hash_desc);
        $code   = $self->get_symbol($code_desc)   if $self->has_symbol($code_desc);
    }
    else {
        confess "This should never ever ever happen";
    }

    $self->remove_glob($name);

    $self->add_symbol($scalar_desc => $scalar) if defined $scalar;
    $self->add_symbol($array_desc  => $array)  if defined $array;
    $self->add_symbol($hash_desc   => $hash)   if defined $hash;
    $self->add_symbol($code_desc   => $code)   if defined $code;
    $self->add_symbol($io_desc     => $io)     if defined $io;
}

sub list_all_symbols {
    my ($self, $type_filter) = @_;

    my $namespace = $self->namespace;
    return keys %{$namespace} unless defined $type_filter;

    # NOTE:
    # or we can filter based on
    # type (SCALAR|ARRAY|HASH|CODE)
    if ($type_filter eq 'CODE') {
        return grep {
            # any non-typeglob in the symbol table is a constant or stub
            ref(\$namespace->{$_}) ne 'GLOB'
                # regular subs are stored in the CODE slot of the typeglob
                || defined(*{$namespace->{$_}}{CODE})
        } keys %{$namespace};
    }
    elsif ($type_filter eq 'SCALAR') {
        return grep {
            BROKEN_SCALAR_INITIALIZATION
                ? (ref(\$namespace->{$_}) eq 'GLOB'
                      && defined(${*{$namespace->{$_}}{'SCALAR'}}))
                : (do {
                      my $entry = \$namespace->{$_};
                      ref($entry) eq 'GLOB'
                          && B::svref_2object($entry)->SV->isa('B::SV')
                  })
        } keys %{$namespace};
    }
    else {
        return grep {
            ref(\$namespace->{$_}) eq 'GLOB'
                && defined(*{$namespace->{$_}}{$type_filter})
        } keys %{$namespace};
    }
}

sub get_all_symbols {
    my ($self, $type_filter) = @_;

    my $namespace = $self->namespace;
    return { %{$namespace} } unless defined $type_filter;

    return {
        map { $_ => $self->get_symbol({name => $_, type => $type_filter}) }
            $self->list_all_symbols($type_filter)
    }
}

=head1 BUGS

=over 4

=item * remove_symbol also replaces the associated typeglob

This can cause unexpected behavior when doing manipulation at compile time -
removing subroutines will still allow them to be called from within the package
as subroutines (although they will not be available as methods). This can be
considered a feature in some cases (this is how L<namespace::clean> works, for
instance), but should not be relied upon - use C<remove_glob> directly if you
want this behavior.

=item * Some minor memory leaks

The pure perl implementation has a couple minor memory leaks (see the TODO
tests in t/20-leaks.t) that I'm having a hard time tracking down - these may be
core perl bugs, it's hard to tell.

=back

Please report any bugs through RT: email
C<bug-package-stash at rt.cpan.org>, or browse to
L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Package-Stash>.

=head1 SEE ALSO

=over 4

=item * L<Class::MOP::Package>

This module is a factoring out of code that used to live here

=back

=head1 SUPPORT

You can find this documentation for this module with the perldoc command.

    perldoc Package::Stash

You can also look for information at:

=over 4

=item * AnnoCPAN: Annotated CPAN documentation

L<http://annocpan.org/dist/Package-Stash>

=item * CPAN Ratings

L<http://cpanratings.perl.org/d/Package-Stash>

=item * RT: CPAN's request tracker

L<http://rt.cpan.org/NoAuth/Bugs.html?Dist=Package-Stash>

=item * Search CPAN

L<http://search.cpan.org/dist/Package-Stash>

=back

=head1 AUTHOR

Jesse Luehrs <doy at tozt dot net>

Mostly copied from code from L<Class::MOP::Package>, by Stevan Little and the
Moose Cabal.

=begin Pod::Coverage

BROKEN_ISA_ASSIGNMENT
add_symbol
get_all_symbols
get_or_add_symbol
get_symbol
has_symbol
list_all_symbols
name
namespace
new
remove_glob

=end Pod::Coverage

=cut

1;
Commit	Line	Data
2905fb35	1	package Package::Stash::PP;
f10f6217	2	use strict;
f10f6217	3	use warnings;
2905fb35	4	# ABSTRACT: pure perl implementation of the Package::Stash API
f10f6217	5
7ef54f40	6	use B;
f10f6217	7	use Carp qw(confess);
eb53b1bd	8	use Scalar::Util qw(blessed reftype weaken);
dc378b60	9	use Symbol;
	10	# before 5.12, assigning to the ISA glob would make it lose its magical ->isa
	11	# powers
	12	use constant BROKEN_ISA_ASSIGNMENT => ($] < 5.012);
36cbfbad	13	# before 5.10, stashes don't ever seem to drop to a refcount of zero, so
	14	# weakening them isn't helpful
	15	use constant BROKEN_WEAK_STASH => ($] < 5.010);
7ef54f40	16	# before 5.10, the scalar slot was always treated as existing if the
	17	# glob existed
	18	use constant BROKEN_SCALAR_INITIALIZATION => ($] < 5.010);
d93368f6	19	# add_method on anon stashes triggers rt.perl #1804 otherwise
	20	# fixed in perl commit v5.13.3-70-g0fe688f
	21	use constant BROKEN_GLOB_ASSIGNMENT => ($] < 5.013004);
f4979588	22
f4979588	23	=head1 SYNOPSIS
f4979588	24
2905fb35	25	use Package::Stash;
f4979588	26
	27	=head1 DESCRIPTION
	28
2905fb35	29	This is a backend for L<Package::Stash> implemented in pure perl, for those without a compiler or who would like to use this inline in scripts.
f4979588	30
	31	=cut
	32
f10f6217	33	sub new {
f10f6217	34	my $class = shift;
e55970bc	35	my ($package) = @_;
774f4f10	36
91a61819	37	if (!defined($package) \|\| (ref($package) && reftype($package) ne 'HASH')) {
774f4f10	38	confess "Package::Stash->new must be passed the name of the "
	39	. "package to access";
	40	}
91a61819	41	elsif (ref($package) && reftype($package) eq 'HASH') {
d93368f6	42	confess "The PP implementation of Package::Stash does not support "
	43	. "anonymous stashes before perl 5.14"
	44	if BROKEN_GLOB_ASSIGNMENT;
	45
91a61819	46	return bless {
	47	'namespace' => $package,
	48	}, $class;
774f4f10	49	}
91a61819	50	elsif ($package =~ /\A[0-9A-Z_a-z]+(?:::[0-9A-Z_a-z]+)*\z/) {
	51	return bless {
	52	'package' => $package,
	53	}, $class;
	54	}
	55	else {
ed131e41	56	confess "$package is not a module name";
ed131e41	57	}
774f4f10	58
f10f6217	59	}
	60
	61	sub name {
2905fb35	62	confess "Can't call name as a class method"
2905fb35	63	unless blessed($_[0]);
91a61819	64	confess "Can't get the name of an anonymous package"
91a61819	65	unless defined($_[0]->{package});
f10f6217	66	return $_[0]->{package};
	67	}
	68
	69	sub namespace {
2905fb35	70	confess "Can't call namespace as a class method"
2905fb35	71	unless blessed($_[0]);
eb53b1bd	72
36cbfbad	73	if (BROKEN_WEAK_STASH) {
eb53b1bd	74	no strict 'refs';
36cbfbad	75	return \%{$_[0]->name . '::'};
eb53b1bd	76	}
36cbfbad	77	else {
36cbfbad	78	return $_[0]->{namespace} if defined $_[0]->{namespace};
eb53b1bd	79
36cbfbad	80	{
	81	no strict 'refs';
	82	$_[0]->{namespace} = \%{$_[0]->name . '::'};
	83	}
	84
	85	weaken($_[0]->{namespace});
eb53b1bd	86
36cbfbad	87	return $_[0]->{namespace};
36cbfbad	88	}
f10f6217	89	}
	90
	91	{
	92	my %SIGIL_MAP = (
	93	'$' => 'SCALAR',
	94	'@' => 'ARRAY',
	95	'%' => 'HASH',
	96	'&' => 'CODE',
56a29840	97	'' => 'IO',
f10f6217	98	);
	99
	100	sub _deconstruct_variable_name {
	101	my ($self, $variable) = @_;
	102
6a42a16c	103	my @ret;
	104	if (ref($variable) eq 'HASH') {
	105	@ret = @{$variable}{qw[name sigil type]};
	106	}
	107	else {
	108	(defined $variable && length $variable)
	109	\|\| confess "You must pass a variable name";
	110
	111	my $sigil = substr($variable, 0, 1, '');
	112
	113	if (exists $SIGIL_MAP{$sigil}) {
	114	@ret = ($variable, $sigil, $SIGIL_MAP{$sigil});
	115	}
	116	else {
	117	@ret = ("${sigil}${variable}", '', $SIGIL_MAP{''});
	118	}
	119	}
f10f6217	120
875d2d1d	121	# XXX in pure perl, this will access things in inner packages,
	122	# in xs, this will segfault - probably look more into this at
	123	# some point
6a42a16c	124	($ret[0] !~ /::/)
875d2d1d	125	\|\| confess "Variable names may not contain ::";
875d2d1d	126
6a42a16c	127	return @ret;
f10f6217	128	}
	129	}
	130
3634ce60	131	sub _valid_for_type {
	132	my $self = shift;
	133	my ($value, $type) = @_;
	134	if ($type eq 'HASH' \|\| $type eq 'ARRAY'
	135	\|\| $type eq 'IO' \|\| $type eq 'CODE') {
	136	return reftype($value) eq $type;
	137	}
	138	else {
	139	my $ref = reftype($value);
d173d3a3	140	return !defined($ref) \|\| $ref eq 'SCALAR' \|\| $ref eq 'REF' \|\| $ref eq 'LVALUE' \|\| $ref eq 'REGEXP' \|\| $ref eq 'VSTRING';
3634ce60	141	}
	142	}
	143
2905fb35	144	sub add_symbol {
640de369	145	my ($self, $variable, $initial_value, %opts) = @_;
f10f6217	146
6a42a16c	147	my ($name, $sigil, $type) = $self->_deconstruct_variable_name($variable);
f10f6217	148
3634ce60	149	if (@_ > 2) {
	150	$self->_valid_for_type($initial_value, $type)
	151	\|\| confess "$initial_value is not of type $type";
3634ce60	152
4ada57e0	153	# cheap fail-fast check for PERLDBf_SUBLINE and '&'
4ada57e0	154	if ($^P and $^P & 0x10 && $sigil eq '&') {
640de369	155	my $filename = $opts{filename};
640de369	156	my $first_line_num = $opts{first_line_num};
4ada57e0	157
640de369	158	(undef, $filename, $first_line_num) = caller
4ada57e0	159	if not defined $filename;
640de369	160
640de369	161	my $last_line_num = $opts{last_line_num} \|\| ($first_line_num \|\|= 0);
4ada57e0	162
4ada57e0	163	# http://perldoc.perl.org/perldebguts.html#Debugger-Internals
50419d91	164	$DB::sub{$self->name . '::' . $name} = "$filename:$first_line_num-$last_line_num";
4ada57e0	165	}
4ada57e0	166	}
f10f6217	167
d93368f6	168	if (BROKEN_GLOB_ASSIGNMENT) {
	169	if (@_ > 2) {
	170	no strict 'refs';
	171	*{ $self->name . '::' . $name } = ref $initial_value
	172	? $initial_value : \$initial_value;
	173	}
	174	else {
	175	no strict 'refs';
	176	*{ $self->name . '::' . $name };
	177	}
	178	}
	179	else {
	180	my $namespace = $self->namespace;
	181	$namespace->{$name} \|\|= *{ Symbol::gensym() };
0f40e41f	182
d93368f6	183	if (@_ > 2) {
	184	*{ $namespace->{$name} } = ref $initial_value
	185	? $initial_value : \$initial_value;
	186	}
0f40e41f	187	}
f10f6217	188	}
f10f6217	189
2905fb35	190	sub remove_glob {
f10f6217	191	my ($self, $name) = @_;
65b8253b	192	delete $self->namespace->{$name};
f10f6217	193	}
f10f6217	194
2905fb35	195	sub has_symbol {
f10f6217	196	my ($self, $variable) = @_;
f10f6217	197
6a42a16c	198	my ($name, $sigil, $type) = $self->_deconstruct_variable_name($variable);
f10f6217	199
	200	my $namespace = $self->namespace;
	201
	202	return unless exists $namespace->{$name};
	203
	204	my $entry_ref = \$namespace->{$name};
	205	if (reftype($entry_ref) eq 'GLOB') {
f7543739	206	if ($type eq 'SCALAR') {
7ef54f40	207	if (BROKEN_SCALAR_INITIALIZATION) {
	208	return defined ${ *{$entry_ref}{$type} };
	209	}
	210	else {
	211	return B::svref_2object($entry_ref)->SV->isa('B::SV');
	212	}
f7543739	213	}
	214	else {
	215	return defined *{$entry_ref}{$type};
	216	}
f10f6217	217	}
	218	else {
	219	# a symbol table entry can be -1 (stub), string (stub with prototype),
	220	# or reference (constant)
	221	return $type eq 'CODE';
	222	}
	223	}
	224
2905fb35	225	sub get_symbol {
e55803fc	226	my ($self, $variable, %opts) = @_;
f10f6217	227
6a42a16c	228	my ($name, $sigil, $type) = $self->_deconstruct_variable_name($variable);
f10f6217	229
	230	my $namespace = $self->namespace;
	231
7486ccf3	232	if (!exists $namespace->{$name}) {
dc378b60	233	if ($opts{vivify}) {
	234	if ($type eq 'ARRAY') {
	235	if (BROKEN_ISA_ASSIGNMENT) {
2905fb35	236	$self->add_symbol(
dc378b60	237	$variable,
	238	$name eq 'ISA' ? () : ([])
	239	);
	240	}
	241	else {
2905fb35	242	$self->add_symbol($variable, []);
dc378b60	243	}
	244	}
	245	elsif ($type eq 'HASH') {
2905fb35	246	$self->add_symbol($variable, {});
dc378b60	247	}
dc378b60	248	elsif ($type eq 'SCALAR') {
2905fb35	249	$self->add_symbol($variable);
dc378b60	250	}
dc378b60	251	elsif ($type eq 'IO') {
2905fb35	252	$self->add_symbol($variable, Symbol::geniosym);
dc378b60	253	}
	254	elsif ($type eq 'CODE') {
	255	confess "Don't know how to vivify CODE variables";
	256	}
	257	else {
	258	confess "Unknown type $type in vivication";
	259	}
5d3589c8	260	}
e55803fc	261	else {
4723417a	262	return undef;
e55803fc	263	}
30d1a098	264	}
f10f6217	265
	266	my $entry_ref = \$namespace->{$name};
	267
	268	if (ref($entry_ref) eq 'GLOB') {
	269	return *{$entry_ref}{$type};
	270	}
	271	else {
	272	if ($type eq 'CODE') {
d6213159	273	# XXX we should really be able to support arbitrary anonymous
d6213159	274	# stashes here... (not just via Package::Anon)
d93368f6	275	if (!BROKEN_GLOB_ASSIGNMENT
	276	&& blessed($namespace)
	277	&& $namespace->isa('Package::Anon')) {
d6213159	278	# ->can will call gv_init for us
	279	$namespace->bless(\(my $foo))->can($name);
	280	return *{ $namespace->{$name} }{CODE};
	281	}
	282	else {
	283	no strict 'refs';
	284	return \&{ $self->name . '::' . $name };
	285	}
f10f6217	286	}
	287	else {
	288	return undef;
	289	}
	290	}
	291	}
	292
2905fb35	293	sub get_or_add_symbol {
e55803fc	294	my $self = shift;
2905fb35	295	$self->get_symbol(@_, vivify => 1);
e55803fc	296	}
e55803fc	297
2905fb35	298	sub remove_symbol {
f10f6217	299	my ($self, $variable) = @_;
f10f6217	300
6a42a16c	301	my ($name, $sigil, $type) = $self->_deconstruct_variable_name($variable);
f10f6217	302
f10f6217	303	# FIXME:
9a3d1390	304	# no doubt this is grossly inefficient and
f10f6217	305	# could be done much easier and faster in XS
f10f6217	306
b1a00d0e	307	my ($scalar_desc, $array_desc, $hash_desc, $code_desc, $io_desc) = (
f10f6217	308	{ sigil => '$', type => 'SCALAR', name => $name },
	309	{ sigil => '@', type => 'ARRAY', name => $name },
	310	{ sigil => '%', type => 'HASH', name => $name },
	311	{ sigil => '&', type => 'CODE', name => $name },
b1a00d0e	312	{ sigil => '', type => 'IO', name => $name },
f10f6217	313	);
f10f6217	314
b1a00d0e	315	my ($scalar, $array, $hash, $code, $io);
f10f6217	316	if ($type eq 'SCALAR') {
2905fb35	317	$array = $self->get_symbol($array_desc) if $self->has_symbol($array_desc);
	318	$hash = $self->get_symbol($hash_desc) if $self->has_symbol($hash_desc);
	319	$code = $self->get_symbol($code_desc) if $self->has_symbol($code_desc);
	320	$io = $self->get_symbol($io_desc) if $self->has_symbol($io_desc);
f10f6217	321	}
f10f6217	322	elsif ($type eq 'ARRAY') {
7ef54f40	323	$scalar = $self->get_symbol($scalar_desc) if $self->has_symbol($scalar_desc) \|\| BROKEN_SCALAR_INITIALIZATION;
2905fb35	324	$hash = $self->get_symbol($hash_desc) if $self->has_symbol($hash_desc);
	325	$code = $self->get_symbol($code_desc) if $self->has_symbol($code_desc);
	326	$io = $self->get_symbol($io_desc) if $self->has_symbol($io_desc);
f10f6217	327	}
f10f6217	328	elsif ($type eq 'HASH') {
7ef54f40	329	$scalar = $self->get_symbol($scalar_desc) if $self->has_symbol($scalar_desc) \|\| BROKEN_SCALAR_INITIALIZATION;
2905fb35	330	$array = $self->get_symbol($array_desc) if $self->has_symbol($array_desc);
	331	$code = $self->get_symbol($code_desc) if $self->has_symbol($code_desc);
	332	$io = $self->get_symbol($io_desc) if $self->has_symbol($io_desc);
f10f6217	333	}
f10f6217	334	elsif ($type eq 'CODE') {
7ef54f40	335	$scalar = $self->get_symbol($scalar_desc) if $self->has_symbol($scalar_desc) \|\| BROKEN_SCALAR_INITIALIZATION;
2905fb35	336	$array = $self->get_symbol($array_desc) if $self->has_symbol($array_desc);
	337	$hash = $self->get_symbol($hash_desc) if $self->has_symbol($hash_desc);
	338	$io = $self->get_symbol($io_desc) if $self->has_symbol($io_desc);
b1a00d0e	339	}
b1a00d0e	340	elsif ($type eq 'IO') {
7ef54f40	341	$scalar = $self->get_symbol($scalar_desc) if $self->has_symbol($scalar_desc) \|\| BROKEN_SCALAR_INITIALIZATION;
2905fb35	342	$array = $self->get_symbol($array_desc) if $self->has_symbol($array_desc);
	343	$hash = $self->get_symbol($hash_desc) if $self->has_symbol($hash_desc);
	344	$code = $self->get_symbol($code_desc) if $self->has_symbol($code_desc);
f10f6217	345	}
	346	else {
	347	confess "This should never ever ever happen";
	348	}
	349
2905fb35	350	$self->remove_glob($name);
f10f6217	351
7ef54f40	352	$self->add_symbol($scalar_desc => $scalar) if defined $scalar;
2905fb35	353	$self->add_symbol($array_desc => $array) if defined $array;
	354	$self->add_symbol($hash_desc => $hash) if defined $hash;
	355	$self->add_symbol($code_desc => $code) if defined $code;
	356	$self->add_symbol($io_desc => $io) if defined $io;
f10f6217	357	}
f10f6217	358
2905fb35	359	sub list_all_symbols {
f10f6217	360	my ($self, $type_filter) = @_;
	361
	362	my $namespace = $self->namespace;
	363	return keys %{$namespace} unless defined $type_filter;
	364
	365	# NOTE:
9a3d1390	366	# or we can filter based on
f10f6217	367	# type (SCALAR\|ARRAY\|HASH\|CODE)
	368	if ($type_filter eq 'CODE') {
	369	return grep {
25c87f5c	370	# any non-typeglob in the symbol table is a constant or stub
	371	ref(\$namespace->{$_}) ne 'GLOB'
	372	# regular subs are stored in the CODE slot of the typeglob
d1f721b3	373	\|\| defined(*{$namespace->{$_}}{CODE})
	374	} keys %{$namespace};
	375	}
	376	elsif ($type_filter eq 'SCALAR') {
	377	return grep {
7ef54f40	378	BROKEN_SCALAR_INITIALIZATION
	379	? (ref(\$namespace->{$_}) eq 'GLOB'
	380	&& defined(${*{$namespace->{$_}}{'SCALAR'}}))
	381	: (do {
	382	my $entry = \$namespace->{$_};
	383	ref($entry) eq 'GLOB'
	384	&& B::svref_2object($entry)->SV->isa('B::SV')
	385	})
d1f721b3	386	} keys %{$namespace};
	387	}
	388	else {
	389	return grep {
	390	ref(\$namespace->{$_}) eq 'GLOB'
	391	&& defined(*{$namespace->{$_}}{$type_filter})
f10f6217	392	} keys %{$namespace};
f10f6217	393	}
f10f6217	394	}
f4979588	395
2905fb35	396	sub get_all_symbols {
	397	my ($self, $type_filter) = @_;
	398
	399	my $namespace = $self->namespace;
	400	return { %{$namespace} } unless defined $type_filter;
	401
	402	return {
	403	map { $_ => $self->get_symbol({name => $_, type => $type_filter}) }
	404	$self->list_all_symbols($type_filter)
	405	}
	406	}
	407
0992f4ec	408	=head1 BUGS
0992f4ec	409
2905fb35	410	=over 4
2905fb35	411
2905fb35	412	=item * remove_symbol also replaces the associated typeglob
	413
	414	This can cause unexpected behavior when doing manipulation at compile time -
	415	removing subroutines will still allow them to be called from within the package
	416	as subroutines (although they will not be available as methods). This can be
	417	considered a feature in some cases (this is how L<namespace::clean> works, for
	418	instance), but should not be relied upon - use C<remove_glob> directly if you
	419	want this behavior.
	420
cdb543b5	421	=item * Some minor memory leaks
	422
	423	The pure perl implementation has a couple minor memory leaks (see the TODO
	424	tests in t/20-leaks.t) that I'm having a hard time tracking down - these may be
	425	core perl bugs, it's hard to tell.
	426
2905fb35	427	=back
0992f4ec	428
	429	Please report any bugs through RT: email
	430	C<bug-package-stash at rt.cpan.org>, or browse to
	431	L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Package-Stash>.
	432
f4979588	433	=head1 SEE ALSO
f4979588	434
f4979588	435	=over 4
f4979588	436
988beb41	437	=item * L<Class::MOP::Package>
f4979588	438
988beb41	439	This module is a factoring out of code that used to live here
f4979588	440
	441	=back
	442
0992f4ec	443	=head1 SUPPORT
	444
	445	You can find this documentation for this module with the perldoc command.
	446
	447	perldoc Package::Stash
	448
	449	You can also look for information at:
	450
	451	=over 4
	452
	453	=item * AnnoCPAN: Annotated CPAN documentation
	454
	455	L<http://annocpan.org/dist/Package-Stash>
	456
	457	=item * CPAN Ratings
	458
	459	L<http://cpanratings.perl.org/d/Package-Stash>
	460
	461	=item * RT: CPAN's request tracker
	462
	463	L<http://rt.cpan.org/NoAuth/Bugs.html?Dist=Package-Stash>
	464
	465	=item * Search CPAN
	466
	467	L<http://search.cpan.org/dist/Package-Stash>
	468
	469	=back
	470
	471	=head1 AUTHOR
	472
	473	Jesse Luehrs <doy at tozt dot net>
	474
	475	Mostly copied from code from L<Class::MOP::Package>, by Stevan Little and the
	476	Moose Cabal.
	477
a912fc4b	478	=begin Pod::Coverage
	479
	480	BROKEN_ISA_ASSIGNMENT
	481	add_symbol
	482	get_all_symbols
	483	get_or_add_symbol
	484	get_symbol
	485	has_symbol
	486	list_all_symbols
	487	name
	488	namespace
	489	new
	490	remove_glob
	491
	492	=end Pod::Coverage
	493
f4979588	494	=cut
	495
	496	1;