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. A common use would be a module
54 exporting an "import" method along with some functions:
56 use ModuleExportingImport;
57 use namespace::clean -except => [qw( import )];
60 You shouldn't need to call any of these. Just "use" the package at the
64 Makes a snapshot of the current defined functions and registers a
65 Filter::EOF cleanup routine to remove those symbols at the end of the
69 This method will be called when you do a
73 It will start a new section of code that defines functions to clean up.
76 This returns a reference to a hash in a passed package containing
77 information about function names included and excluded from removal.
80 Takes a class as argument and returns all currently defined functions in
81 it as a hash reference with the function name as key and a typeglob
82 reference to the symbol as value.
84 IMPLEMENTATION DETAILS
85 This module works through the effect that a
87 delete $SomePackage::{foo};
89 will remove the "foo" symbol from $SomePackage for run time lookups
90 (e.g., method calls) but will leave the entry alive to be called by
91 already resolved names in the package itself.
93 A test file has been added to the perl core to ensure that this
94 behaviour will be stable in future releases.
96 Just for completeness sake, if you want to remove the symbol completely,
103 Robert 'phaylon' Sedlacek "<rs@474.at>", with many thanks to Matt S
104 Trout for the inspiration on the whole idea.
107 This program is free software; you can redistribute it and/or modify it
108 under the same terms as perl itself.