package autovivification;
-use 5.008;
+use 5.008003;
use strict;
use warnings;
=head1 VERSION
-Version 0.03
+Version 0.10
=cut
our $VERSION;
BEGIN {
- $VERSION = '0.03';
+ $VERSION = '0.10';
}
=head1 SYNOPSIS
=head1 METHODS
-=head2 C<unimport @opts>
+=head2 C<unimport>
-Magically called when C<no autovivification> is encountered.
+ no autovivification; # defaults to qw<fetch exists delete>
+ no autovivification qw<fetch store exists delete>;
+ no autovivification 'warn';
+ no autovivification 'strict';
+
+Magically called when C<no autovivification @opts> is encountered.
Enables the features given in C<@opts>, which can be :
=over 4
C<'fetch'>
-Turn off autovivification for rvalue dereferencing expressions, such as C<< $value = $hashref->{key}[$idx]{$field} >>, C<< keys %{$hashref->{key}} >> or C<< values %{$hashref->{key}} >>.
-Starting from perl C<5.11>, it also covers C<leys> and C<values> on array references.
+Turns off autovivification for rvalue dereferencing expressions, such as :
+
+ $value = $arrayref->[$idx]
+ $value = $hashref->{$key}
+ keys %$hashref
+ values %$hashref
+
+Starting from perl C<5.11>, it also covers C<keys> and C<values> on array references :
+
+ keys @$arrayref
+ values @$arrayref
+
When the expression would have autovivified, C<undef> is returned for a plain fetch, while C<keys> and C<values> return C<0> in scalar context and the empty list in list context.
=item *
C<'exists'>
-Turn off autovivification for dereferencing expressions that are parts of an C<exists>, such as C<< exists $hashref->{key}[$idx]{$field} >>.
+Turns off autovivification for dereferencing expressions that are parts of an C<exists>, such as :
+
+ exists $arrayref->[$idx]
+ exists $hashref->{$key}
+
C<''> is returned when the expression would have autovivified.
=item *
C<'delete'>
-Turn off autovivification for dereferencing expressions that are parts of a C<delete>, such as C<< delete $hashref->{key}[$idx]{$field} >>.
+Turns off autovivification for dereferencing expressions that are parts of a C<delete>, such as :
+
+ delete $arrayref->[$idx]
+ delete $hashref->{$key}
+
C<undef> is returned when the expression would have autovivified.
=item *
C<'store'>
-Turn off autovivification for lvalue dereferencing expressions, such as C<< $hashref->{key}[$idx]{$field} = $value >> or C<< for ($hashref->{key}[$idx]{$field}) { ... } >>.
-An exception is thrown if vivification is needed to store the value, which means that effectively you can only assign to levels that are already defined (in the example, this would require C<< $hashref->{key}[$idx] >> to already be a hash reference).
+Turns off autovivification for lvalue dereferencing expressions, such as :
+
+ $arrayref->[$idx] = $value
+ $hashref->{$key} = $value
+ for ($arrayref->[$idx]) { ... }
+ for ($hashref->{$key}) { ... }
+ function($arrayref->[$idx])
+ function($hashref->{$key})
+
+An exception is thrown if vivification is needed to store the value, which means that effectively you can only assign to levels that are already defined.
+In the example, this would require C<$arrayref> (resp. C<$hashref>) to already be an array (resp. hash) reference.
=item *
C<'warn'>
-Emit a warning when an autovivification is avoided.
+Emits a warning when an autovivification is avoided.
=item *
C<'strict'>
-Throw an exception when an autovivification is avoided.
+Throws an exception when an autovivification is avoided.
=back
Each call to C<unimport> adds the specified features to the ones already in use in the current lexical scope.
-When C<@opts> is empty, it defaults to C<qw/fetch exists delete/>.
+When C<@opts> is empty, it defaults to C<< qw<fetch exists delete> >>.
=cut
sub unimport {
shift;
my $hint = _detag($^H{+(__PACKAGE__)}) || 0;
- @_ = qw/fetch exists delete/ unless @_;
+ @_ = qw<fetch exists delete> unless @_;
$hint |= $bits{$_} for grep exists $bits{$_}, @_;
$^H |= 0x00020000;
$^H{+(__PACKAGE__)} = _tag($hint);
();
}
-=head2 C<import @opts>
+=head2 C<import>
+
+ use autovivification; # default Perl behaviour
+ use autovivification qw<fetch store exists delete>;
-Magically called when C<use autovivification> is encountered.
+Magically called when C<use autovivification @opts> is encountered.
Disables the features given in C<@opts>, which can be the same as for L</unimport>.
Each call to C<import> removes the specified features to the ones already in use in the current lexical scope.
();
}
+=head1 CONSTANTS
+
+=head2 C<A_THREADSAFE>
+
+True iff the module could have been built with thread-safety features enabled.
+This constant only has a meaning with your perl is threaded ; otherwise, it'll always be false.
+
+=head2 C<A_FORKSAFE>
+
+True iff this module could have been built with fork-safety features enabled.
+This will always be true except on Windows where it's false for perl 5.10.0 and below.
+
=head1 CAVEATS
The pragma doesn't apply when one dereferences the returned value of an array or hash slice, as in C<< @array[$id]->{member} >> or C<< @hash{$key}->{member} >>.
=head1 DEPENDENCIES
-L<perl> 5.8.
+L<perl> 5.8.3.
+
+A C compiler.
+This module may happen to build with a C++ compiler as well, but don't rely on it, as no guarantee is made in this regard.
L<XSLoader> (standard since perl 5.006).
=head1 COPYRIGHT & LICENSE
-Copyright 2009,2010 Vincent Pit, all rights reserved.
+Copyright 2009,2010,2011,2012 Vincent Pit, all rights reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
projects / perl / modules / autovivification.git / blobdiff