NAME
- namespace::clean - Keep imports out of your namespace
+ namespace::clean - Keep imports and functions out of your namespace
VERSION
- 0.02
+ 0.03
SYNOPSIS
package Foo;
use warnings;
use strict;
- use Carp qw(croak); # will be removed
+ use Carp qw(croak); # 'croak' will be removed
- sub bar { 23 } # will be removed
+ sub bar { 23 } # 'bar' will be removed
+ # remove all previously defined functions
use namespace::clean;
- sub baz { bar() } # still defined, 'bar' still bound
+ sub baz { bar() } # 'baz' still defined, 'bar' still bound
+ # begin to collection function names from here again
no namespace::clean;
- sub quux { baz() } # will be removed again
+ sub quux { baz() } # 'quux' will be removed
+ # remove all functions defined after the 'no' unimport
use namespace::clean;
- ### Will print:
- # No
- # No
- # Yes
- # No
+ # Will print: 'No', 'No', 'Yes' and 'No'
print +(__PACKAGE__->can('croak') ? 'Yes' : 'No'), "\n";
print +(__PACKAGE__->can('bar') ? 'Yes' : 'No'), "\n";
print +(__PACKAGE__->can('baz') ? 'Yes' : 'No'), "\n";
When you define a function, or import one, into a Perl package, it will
naturally also be available as a method. This does not per se cause
problems, but it can complicate subclassing and, for example, plugin
- classes that are included by loading them as base classes.
+ classes that are included via multiple inheritance by loading them as
+ base classes.
The "namespace::clean" pragma will remove all previously declared or
- imported symbols at the end of the current package's compile cycle. This
- means that functions are already bound by their name, and calls to them
- still work. But they will not be available as methods on your class or
- instances.
+ imported symbols at the end of the current package's compile cycle.
+ Functions called in the package itself will still be bound by their
+ name, but they won't show up as methods on your class or instances.
+
+ By unimporting via "no" you can tell "namespace::clean" to start
+ collecting functions for the next "use namespace::clean;" specification.
METHODS
You shouldn't need to call any of these. Just "use" the package at the
import
Makes a snapshot of the current defined functions and registers a
- Filter::EOF cleanup routine to remove those symbols from the package at
- the end of the compile-time.
+ Filter::EOF cleanup routine to remove those symbols at the end of the
+ compile-time.
unimport
This method will be called when you do a
It will start a new section of code that defines functions to clean up.
get_class_store
- This returns a reference to a hash in your package containing
+ This returns a reference to a hash in a passed package containing
information about function names included and excluded from removal.
get_functions
it as a hash reference with the function name as key and a typeglob
reference to the symbol as value.
+IMPLEMENTATION DETAILS
+ This module works through the effect that a
+
+ delete $SomePackage::{foo};
+
+ will remove the "foo" symbol from $SomePackage for run time lookups
+ (e.g., method calls) but will leave the entry alive to be called by
+ already resolved names in the package itself.
+
+ A test file has been added to the perl core to ensure that this
+ behaviour will be stable in future releases.
+
+ Just for completeness sake, if you want to remove the symbol completely,
+ use "undef" instead.
+
SEE ALSO
Filter::EOF
=head1 NAME
-namespace::clean - Keep imports out of your namespace
+namespace::clean - Keep imports and functions out of your namespace
=cut
=head1 VERSION
-0.02
+0.03
=cut
-$VERSION = 0.02;
+$VERSION = 0.03;
$STORAGE_VAR = '__NAMESPACE_CLEAN_STORAGE';
=head1 SYNOPSIS
use warnings;
use strict;
- use Carp qw(croak); # will be removed
+ use Carp qw(croak); # 'croak' will be removed
- sub bar { 23 } # will be removed
+ sub bar { 23 } # 'bar' will be removed
+ # remove all previously defined functions
use namespace::clean;
- sub baz { bar() } # still defined, 'bar' still bound
+ sub baz { bar() } # 'baz' still defined, 'bar' still bound
+ # begin to collection function names from here again
no namespace::clean;
- sub quux { baz() } # will be removed again
+ sub quux { baz() } # 'quux' will be removed
+ # remove all functions defined after the 'no' unimport
use namespace::clean;
- ### Will print:
- # No
- # No
- # Yes
- # No
+ # Will print: 'No', 'No', 'Yes' and 'No'
print +(__PACKAGE__->can('croak') ? 'Yes' : 'No'), "\n";
print +(__PACKAGE__->can('bar') ? 'Yes' : 'No'), "\n";
print +(__PACKAGE__->can('baz') ? 'Yes' : 'No'), "\n";
When you define a function, or import one, into a Perl package, it will
naturally also be available as a method. This does not per se cause
problems, but it can complicate subclassing and, for example, plugin
-classes that are included by loading them as base classes.
+classes that are included via multiple inheritance by loading them as
+base classes.
The C<namespace::clean> pragma will remove all previously declared or
imported symbols at the end of the current package's compile cycle.
-This means that functions are already bound by their name, and calls to
-them still work. But they will not be available as methods on your class
-or instances.
+Functions called in the package itself will still be bound by their
+name, but they won't show up as methods on your class or instances.
+
+By unimporting via C<no> you can tell C<namespace::clean> to start
+collecting functions for the next C<use namespace::clean;> specification.
=head1 METHODS
You shouldn't need to call any of these. Just C<use> the package at the
appropriate place.
+=cut
+
=head2 import
Makes a snapshot of the current defined functions and registers a
-L<Filter::EOF> cleanup routine to remove those symbols from the package
-at the end of the compile-time.
+L<Filter::EOF> cleanup routine to remove those symbols at the end
+of the compile-time.
=cut
sub import {
my ($pragma) = @_;
+ # calling class, all current functions and our storage
my $cleanee = caller;
my $functions = $pragma->get_functions($cleanee);
my $store = $pragma->get_class_store($cleanee);
+ # register symbols for removal, if they have a CODE entry
for my $f (keys %$functions) {
next unless $functions->{ $f }
and *{ $functions->{ $f } }{CODE};
$store->{remove}{ $f } = 1;
}
+ # register EOF handler on first call to import
unless ($store->{handler_is_installed}) {
Filter::EOF->on_eof_call(sub {
for my $f (keys %{ $store->{remove} }) {
sub unimport {
my ($pragma) = @_;
+ # the calling class, the current functions and our storage
my $cleanee = caller;
my $functions = $pragma->get_functions($cleanee);
my $store = $pragma->get_class_store($cleanee);
+ # register all unknown previous functions as excluded
for my $f (keys %$functions) {
next if $store->{remove}{ $f }
or $store->{exclude}{ $f };
=head2 get_class_store
-This returns a reference to a hash in your package containing information
-about function names included and excluded from removal.
+This returns a reference to a hash in a passed package containing
+information about function names included and excluded from removal.
=cut
my ($pragma, $class) = @_;
return {
- map { @$_ }
- grep { *{ $_->[1] }{CODE} }
- map { [$_, qualify_to_ref( $_, $class )] }
- grep { $_ !~ /::$/ }
- do { no strict 'refs'; keys %{ "${class}::" } }
+ map { @$_ } # key => value
+ grep { *{ $_->[1] }{CODE} } # only functions
+ map { [$_, qualify_to_ref( $_, $class )] } # get globref
+ grep { $_ !~ /::$/ } # no packages
+ do { no strict 'refs'; keys %{ "${class}::" } } # symbol entries
};
}
+=head1 IMPLEMENTATION DETAILS
+
+This module works through the effect that a
+
+ delete $SomePackage::{foo};
+
+will remove the C<foo> symbol from C<$SomePackage> for run time lookups
+(e.g., method calls) but will leave the entry alive to be called by
+already resolved names in the package itself.
+
+A test file has been added to the perl core to ensure that this behaviour
+will be stable in future releases.
+
+Just for completeness sake, if you want to remove the symbol completely,
+use C<undef> instead.
+
=head1 SEE ALSO
L<Filter::EOF>