2 namespace::clean - Keep imports and functions out of your namespace
12 use Carp qw(croak); # 'croak' will be removed
14 sub bar { 23 } # 'bar' will be removed
16 # remove all previously defined functions
19 sub baz { bar() } # 'baz' still defined, 'bar' still bound
21 # begin to collection function names from here again
24 sub quux { baz() } # 'quux' will be removed
26 # remove all functions defined after the 'no' unimport
29 # Will print: 'No', 'No', 'Yes' and 'No'
30 print +(__PACKAGE__->can('croak') ? 'Yes' : 'No'), "\n";
31 print +(__PACKAGE__->can('bar') ? 'Yes' : 'No'), "\n";
32 print +(__PACKAGE__->can('baz') ? 'Yes' : 'No'), "\n";
33 print +(__PACKAGE__->can('quux') ? 'Yes' : 'No'), "\n";
38 When you define a function, or import one, into a Perl package, it will
39 naturally also be available as a method. This does not per se cause
40 problems, but it can complicate subclassing and, for example, plugin
41 classes that are included via multiple inheritance by loading them as
44 The "namespace::clean" pragma will remove all previously declared or
45 imported symbols at the end of the current package's compile cycle.
46 Functions called in the package itself will still be bound by their
47 name, but they won't show up as methods on your class or instances.
49 By unimporting via "no" you can tell "namespace::clean" to start
50 collecting functions for the next "use namespace::clean;" specification.
52 You can use the "-except" flag to tell "namespace::clean" that you don't
53 want it to remove a certain function or method. A common use would be a
54 module exporting an "import" method along with some functions:
56 use ModuleExportingImport;
57 use namespace::clean -except => [qw( import )];
59 If you just want to "-except" a single sub, you can pass it directly.
60 For more than one value you have to use an array reference.
63 When using "namespace::clean" together with Moose you want to keep the
64 installed "meta" method. So your classes should look like:
68 use namespace::clean -except => 'meta';
71 Same goes for Moose::Role.
74 You shouldn't need to call any of these. Just "use" the package at the
78 Makes a snapshot of the current defined functions and installs a
79 Scope::Guard in the current scope to invoke the cleanups.
82 This method will be called when you do a
86 It will start a new section of code that defines functions to clean up.
89 This returns a reference to a hash in a passed package containing
90 information about function names included and excluded from removal.
93 Takes a class as argument and returns all currently defined functions in
94 it as a hash reference with the function name as key and a typeglob
95 reference to the symbol as value.
97 IMPLEMENTATION DETAILS
98 This module works through the effect that a
100 delete $SomePackage::{foo};
102 will remove the "foo" symbol from $SomePackage for run time lookups
103 (e.g., method calls) but will leave the entry alive to be called by
104 already resolved names in the package itself. "namespace::clean" will
105 restore and therefor in effect keep all glob slots that aren't "CODE".
107 A test file has been added to the perl core to ensure that this
108 behaviour will be stable in future releases.
110 Just for completeness sake, if you want to remove the symbol completely,
117 Robert 'phaylon' Sedlacek "<rs@474.at>", with many thanks to Matt S
118 Trout for the inspiration on the whole idea.
121 This program is free software; you can redistribute it and/or modify it
122 under the same terms as perl itself.