my $stash = Package::Stash->new('Foo');
$stash->add_symbol('%foo', {bar => 1});
# $Foo::foo{bar} == 1
$stash->has_symbol('$foo') # false
my $namespace = $stash->namespace;
*{ $namespace->{foo} }{HASH} # {bar => 1}
NOTE: Most methods in this class require a variable specification that includes a sigil. If this sigil is absent, it is assumed to represent the IO slot.
Due to limitations in the typeglob API available to perl code, and to typeglob manipulation in perl being quite slow, this module provides two implementations - one in pure perl, and one using XS. The XS implementation is to be preferred for most usages; the pure perl one is provided for cases where XS modules are not a possibility. The current implementation in use can be set by setting $ENV{PACKAGE_STASH_IMPLEMENTATION} or $Package::Stash::IMPLEMENTATION before loading Package::Stash (with the environment variable taking precedence), otherwise, it will use the XS implementation if possible, falling back to the pure perl one.
Package::Stash->new('Foo')->add_symbol('%foo')
will create %Foo::foo.
Valid options (all optional) are "filename", "first_line_num", and "last_line_num".
$opts{filename}, $opts{first_line_num}, and $opts{last_line_num} can be used to indicate where the symbol should be regarded as having been defined. Currently these values are only used if the symbol is a subroutine ('"&"' sigil) and only if "$^P & 0x10" is true, in which case the special %DB::sub hash is updated to record the values of "filename", "first_line_num", and "last_line_num" for the subroutine. If these are not passed, their values are inferred (as much as possible) from "caller" information.
This is especially useful for debuggers and profilers, which use %DB::sub to determine where the source code for a subroutine can be found. See <http://perldoc.perl.org/perldebguts.html#Debugger-Internals> for more information about %DB::sub.
my $stash = Package::Stash->new('Some::Namespace');
my $variable = 1;
# $Some::Namespace::name is a copy of $variable
$stash->add_symbol('$name', $variable);
$variable++
# $Some::Namespace::name == 1 , $variable == 2
This will likely confuse people who expect it to work the same as typeglob assignment, which simply creates new references to existing variables.
my $variable = 1;
{
no strict 'refs';
# assign $Package::Stash::name = $variable
*{'Package::Stash::name'} = \$variable;
}
$variable++ # affects both names
If this behaviour is desired when working with Package::Stash, simply pass Package::Stash a scalar ref:
my $stash = Package::Stash->new('Some::Namespace');
my $variable = 1;
# $Some::Namespace::name is now $variable
$stash->add_symbol('$name', \$variable);
$variable++
# $Some::Namespace::name == 2 , $variable == 2
This will be what you want as well if you're ever working with Readonly variables:
use Readonly;
Readonly my $value, 'hello';
$stash->add_symbol('$name', \$value); # reference
print $Some::Namespace::name; # hello
# Tries to modify the read-only 'hello' and dies.
$Some::Namespace::name .= " world";
$stash->add_symbol('$name', $value); # copy
print $Some::Namespace::name; # hello
# No problem, modifying a copy, not the original
$Some::Namespace::name .= " world";
This module is a factoring out of code that used to live here
This is due to a shortcoming within perl itself. See ``Making References'' in perlref point 7 for more information.
Bugs may be submitted through the RT bug tracker <https://rt.cpan.org/Public/Dist/Display.html?Name=Package-Stash> (or bug-Package-Stash@rt.cpan.org <mailto:bug-Package-Stash@rt.cpan.org>).
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.