Commit | Line | Data |
f4979588 |
1 | package Stash::Manip; |
f10f6217 |
2 | use strict; |
3 | use warnings; |
4 | |
5 | use Carp qw(confess); |
6 | use Scalar::Util qw(reftype); |
f4979588 |
7 | |
8 | =head1 NAME |
9 | |
683542f5 |
10 | Stash::Manip - routines for manipulating stashes |
f4979588 |
11 | |
12 | =head1 SYNOPSIS |
13 | |
683542f5 |
14 | my $stash = Stash::Manip->new('Foo'); |
15 | $stash->add_package_symbol('%foo', {bar => 1}); |
16 | # $Foo::foo{bar} == 1 |
17 | $stash->has_package_symbol('$foo') # false |
18 | my $namespace = $stash->namespace; |
19 | *{ $namespace->{foo} }{HASH} # {bar => 1} |
f4979588 |
20 | |
21 | =head1 DESCRIPTION |
22 | |
683542f5 |
23 | Manipulating stashes (Perl's symbol tables) is occasionally necessary, but |
24 | incredibly messy, and easy to get wrong. This module hides all of that behind a |
25 | simple API. |
26 | |
27 | =head1 METHODS |
28 | |
29 | =cut |
30 | |
31 | =head2 new $package_name |
32 | |
33 | Creates a new C<Stash::Manip> object, for the package given as the only |
34 | argument. |
f4979588 |
35 | |
36 | =cut |
37 | |
f10f6217 |
38 | sub new { |
39 | my $class = shift; |
40 | my ($namespace) = @_; |
41 | return bless { package => $namespace }, $class; |
42 | } |
43 | |
683542f5 |
44 | =head2 name |
45 | |
46 | Returns the name of the package that this object represents. |
47 | |
48 | =cut |
49 | |
f10f6217 |
50 | sub name { |
51 | return $_[0]->{package}; |
52 | } |
53 | |
683542f5 |
54 | =head2 namespace |
55 | |
56 | Returns the raw stash itself. |
57 | |
58 | =cut |
59 | |
f10f6217 |
60 | sub namespace { |
61 | # NOTE: |
62 | # because of issues with the Perl API |
63 | # to the typeglob in some versions, we |
64 | # need to just always grab a new |
65 | # reference to the hash here. Ideally |
66 | # we could just store a ref and it would |
67 | # Just Work, but oh well :\ |
68 | no strict 'refs'; |
69 | return \%{$_[0]->name . '::'}; |
70 | } |
71 | |
72 | { |
73 | my %SIGIL_MAP = ( |
74 | '$' => 'SCALAR', |
75 | '@' => 'ARRAY', |
76 | '%' => 'HASH', |
77 | '&' => 'CODE', |
78 | ); |
79 | |
80 | sub _deconstruct_variable_name { |
81 | my ($self, $variable) = @_; |
82 | |
83 | (defined $variable) |
84 | || confess "You must pass a variable name"; |
85 | |
86 | my $sigil = substr($variable, 0, 1, ''); |
87 | |
88 | (defined $sigil) |
89 | || confess "The variable name must include a sigil"; |
90 | |
91 | (exists $SIGIL_MAP{$sigil}) |
92 | || confess "I do not recognize that sigil '$sigil'"; |
93 | |
94 | return ($variable, $sigil, $SIGIL_MAP{$sigil}); |
95 | } |
96 | } |
97 | |
683542f5 |
98 | =head2 add_package_symbol $variable $value |
99 | |
100 | Adds a new package symbol, for the symbol given as C<$variable>, and optionally |
101 | gives it an initial value of C<$value>. C<$variable> should be the name of |
102 | variable including the sigil, so |
103 | |
104 | Stash::Manip->new('Foo')->add_package_symbol('%foo') |
105 | |
106 | will create C<%Foo::foo>. |
107 | |
108 | =cut |
109 | |
f10f6217 |
110 | sub add_package_symbol { |
111 | my ($self, $variable, $initial_value) = @_; |
112 | |
113 | my ($name, $sigil, $type) = ref $variable eq 'HASH' |
114 | ? @{$variable}{qw[name sigil type]} |
115 | : $self->_deconstruct_variable_name($variable); |
116 | |
117 | my $pkg = $self->name; |
118 | |
119 | no strict 'refs'; |
120 | no warnings 'redefine', 'misc', 'prototype'; |
121 | *{$pkg . '::' . $name} = ref $initial_value ? $initial_value : \$initial_value; |
122 | } |
123 | |
683542f5 |
124 | =head2 remove_package_glob $name |
125 | |
126 | Removes all package variables with the given name, regardless of sigil. |
127 | |
128 | =cut |
129 | |
f10f6217 |
130 | sub remove_package_glob { |
131 | my ($self, $name) = @_; |
132 | no strict 'refs'; |
133 | delete ${$self->name . '::'}{$name}; |
134 | } |
135 | |
136 | # ... these functions deal with stuff on the namespace level |
137 | |
683542f5 |
138 | =head2 has_package_symbol $variable |
139 | |
140 | Returns whether or not the given package variable (including sigil) exists. |
141 | |
142 | =cut |
143 | |
f10f6217 |
144 | sub has_package_symbol { |
145 | my ($self, $variable) = @_; |
146 | |
147 | my ($name, $sigil, $type) = ref $variable eq 'HASH' |
148 | ? @{$variable}{qw[name sigil type]} |
149 | : $self->_deconstruct_variable_name($variable); |
150 | |
151 | my $namespace = $self->namespace; |
152 | |
153 | return unless exists $namespace->{$name}; |
154 | |
155 | my $entry_ref = \$namespace->{$name}; |
156 | if (reftype($entry_ref) eq 'GLOB') { |
157 | if ( $type eq 'SCALAR' ) { |
158 | return defined ${ *{$entry_ref}{SCALAR} }; |
159 | } |
160 | else { |
161 | return defined *{$entry_ref}{$type}; |
162 | } |
163 | } |
164 | else { |
165 | # a symbol table entry can be -1 (stub), string (stub with prototype), |
166 | # or reference (constant) |
167 | return $type eq 'CODE'; |
168 | } |
169 | } |
170 | |
683542f5 |
171 | =head2 get_package_symbol $variable |
172 | |
173 | Returns the value of the given package variable (including sigil). |
174 | |
175 | =cut |
176 | |
f10f6217 |
177 | sub get_package_symbol { |
178 | my ($self, $variable) = @_; |
179 | |
180 | my ($name, $sigil, $type) = ref $variable eq 'HASH' |
181 | ? @{$variable}{qw[name sigil type]} |
182 | : $self->_deconstruct_variable_name($variable); |
183 | |
184 | my $namespace = $self->namespace; |
185 | |
186 | # FIXME |
187 | $self->add_package_symbol($variable) |
188 | unless exists $namespace->{$name}; |
189 | |
190 | my $entry_ref = \$namespace->{$name}; |
191 | |
192 | if (ref($entry_ref) eq 'GLOB') { |
193 | return *{$entry_ref}{$type}; |
194 | } |
195 | else { |
196 | if ($type eq 'CODE') { |
197 | no strict 'refs'; |
198 | return \&{ $self->name . '::' . $name }; |
199 | } |
200 | else { |
201 | return undef; |
202 | } |
203 | } |
204 | } |
205 | |
683542f5 |
206 | =head2 remove_package_symbol $variable |
207 | |
208 | Removes the package variable described by C<$variable> (which includes the |
209 | sigil); other variables with the same name but different sigils will be |
210 | untouched. |
211 | |
212 | =cut |
213 | |
f10f6217 |
214 | sub remove_package_symbol { |
215 | my ($self, $variable) = @_; |
216 | |
217 | my ($name, $sigil, $type) = ref $variable eq 'HASH' |
218 | ? @{$variable}{qw[name sigil type]} |
219 | : $self->_deconstruct_variable_name($variable); |
220 | |
221 | # FIXME: |
222 | # no doubt this is grossly inefficient and |
223 | # could be done much easier and faster in XS |
224 | |
225 | my ($scalar_desc, $array_desc, $hash_desc, $code_desc) = ( |
226 | { sigil => '$', type => 'SCALAR', name => $name }, |
227 | { sigil => '@', type => 'ARRAY', name => $name }, |
228 | { sigil => '%', type => 'HASH', name => $name }, |
229 | { sigil => '&', type => 'CODE', name => $name }, |
230 | ); |
231 | |
232 | my ($scalar, $array, $hash, $code); |
233 | if ($type eq 'SCALAR') { |
234 | $array = $self->get_package_symbol($array_desc) if $self->has_package_symbol($array_desc); |
235 | $hash = $self->get_package_symbol($hash_desc) if $self->has_package_symbol($hash_desc); |
236 | $code = $self->get_package_symbol($code_desc) if $self->has_package_symbol($code_desc); |
237 | } |
238 | elsif ($type eq 'ARRAY') { |
239 | $scalar = $self->get_package_symbol($scalar_desc) if $self->has_package_symbol($scalar_desc); |
240 | $hash = $self->get_package_symbol($hash_desc) if $self->has_package_symbol($hash_desc); |
241 | $code = $self->get_package_symbol($code_desc) if $self->has_package_symbol($code_desc); |
242 | } |
243 | elsif ($type eq 'HASH') { |
244 | $scalar = $self->get_package_symbol($scalar_desc) if $self->has_package_symbol($scalar_desc); |
245 | $array = $self->get_package_symbol($array_desc) if $self->has_package_symbol($array_desc); |
246 | $code = $self->get_package_symbol($code_desc) if $self->has_package_symbol($code_desc); |
247 | } |
248 | elsif ($type eq 'CODE') { |
249 | $scalar = $self->get_package_symbol($scalar_desc) if $self->has_package_symbol($scalar_desc); |
250 | $array = $self->get_package_symbol($array_desc) if $self->has_package_symbol($array_desc); |
251 | $hash = $self->get_package_symbol($hash_desc) if $self->has_package_symbol($hash_desc); |
252 | } |
253 | else { |
254 | confess "This should never ever ever happen"; |
255 | } |
256 | |
257 | $self->remove_package_glob($name); |
258 | |
259 | $self->add_package_symbol($scalar_desc => $scalar) if defined $scalar; |
260 | $self->add_package_symbol($array_desc => $array) if defined $array; |
261 | $self->add_package_symbol($hash_desc => $hash) if defined $hash; |
262 | $self->add_package_symbol($code_desc => $code) if defined $code; |
263 | } |
264 | |
683542f5 |
265 | =head2 list_all_package_symbols $type_filter |
266 | |
267 | Returns a list of package variable names in the package, without sigils. If a |
268 | C<type_filter> is passed, it is used to select package variables of a given |
269 | type, where valid types are the slots of a typeglob ('SCALAR', 'CODE', 'HASH', |
270 | etc). |
271 | |
272 | =cut |
273 | |
f10f6217 |
274 | sub list_all_package_symbols { |
275 | my ($self, $type_filter) = @_; |
276 | |
277 | my $namespace = $self->namespace; |
278 | return keys %{$namespace} unless defined $type_filter; |
279 | |
280 | # NOTE: |
281 | # or we can filter based on |
282 | # type (SCALAR|ARRAY|HASH|CODE) |
283 | if ($type_filter eq 'CODE') { |
284 | return grep { |
285 | (ref($namespace->{$_}) |
286 | ? (ref($namespace->{$_}) eq 'SCALAR') |
287 | : (ref(\$namespace->{$_}) eq 'GLOB' |
288 | && defined(*{$namespace->{$_}}{CODE}))); |
289 | } keys %{$namespace}; |
290 | } else { |
291 | return grep { *{$namespace->{$_}}{$type_filter} } keys %{$namespace}; |
292 | } |
293 | } |
f4979588 |
294 | |
295 | =head1 BUGS |
296 | |
297 | No known bugs. |
298 | |
299 | Please report any bugs through RT: email |
300 | C<bug-stash-manip at rt.cpan.org>, or browse to |
301 | L<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Stash-Manip>. |
302 | |
303 | =head1 SEE ALSO |
304 | |
683542f5 |
305 | L<Class::MOP::Package> - this module is a factoring out of code that used to |
306 | live here |
f4979588 |
307 | |
308 | =head1 SUPPORT |
309 | |
310 | You can find this documentation for this module with the perldoc command. |
311 | |
312 | perldoc Stash::Manip |
313 | |
314 | You can also look for information at: |
315 | |
316 | =over 4 |
317 | |
318 | =item * AnnoCPAN: Annotated CPAN documentation |
319 | |
320 | L<http://annocpan.org/dist/Stash-Manip> |
321 | |
322 | =item * CPAN Ratings |
323 | |
324 | L<http://cpanratings.perl.org/d/Stash-Manip> |
325 | |
326 | =item * RT: CPAN's request tracker |
327 | |
328 | L<http://rt.cpan.org/NoAuth/Bugs.html?Dist=Stash-Manip> |
329 | |
330 | =item * Search CPAN |
331 | |
332 | L<http://search.cpan.org/dist/Stash-Manip> |
333 | |
334 | =back |
335 | |
336 | =head1 AUTHOR |
337 | |
338 | Jesse Luehrs <doy at tozt dot net> |
339 | |
683542f5 |
340 | Mostly copied from code from L<Class::MOP::Package>, by Stevan Little and the |
341 | Moose Cabal. |
342 | |
f4979588 |
343 | =head1 COPYRIGHT AND LICENSE |
344 | |
345 | This software is copyright (c) 2010 by Jesse Luehrs. |
346 | |
347 | This is free software; you can redistribute it and/or modify it under |
348 | the same terms as perl itself. |
349 | |
350 | =cut |
351 | |
352 | 1; |