NAME
Package::Stash - routines for manipulating stashes
VERSION
version 0.21
SYNOPSIS
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}
DESCRIPTION
Manipulating stashes (Perl's symbol tables) is occasionally necessary, but incredibly messy, and easy to get wrong. This module hides all of that behind a simple API.
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.
METHODS
new $package_name
Creates a new Package::Stash
object, for the package given as the only argument.
name
Returns the name of the package that this object represents.
namespace
Returns the raw stash itself.
add_symbol $variable $value %opts
Adds a new package symbol, for the symbol given as $variable
, and optionally gives it an initial value of $value
. $variable
should be the name of variable including the sigil, so
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
.
remove_glob $name
Removes all package variables with the given name, regardless of sigil.
has_symbol $variable
Returns whether or not the given package variable (including sigil) exists.
get_symbol $variable
Returns the value of the given package variable (including sigil).
get_or_add_symbol $variable
Like get_symbol
, except that it will return an empty hashref or arrayref if the variable doesn't exist.
remove_symbol $variable
Removes the package variable described by $variable
(which includes the sigil); other variables with the same name but different sigils will be untouched.
list_all_symbols $type_filter
Returns a list of package variable names in the package, without sigils. If a type_filter
is passed, it is used to select package variables of a given type, where valid types are the slots of a typeglob ('SCALAR', 'CODE', 'HASH', etc). Note that if the package contained any BEGIN
blocks, perl will leave an empty typeglob in the BEGIN
slot, so this will show up if no filter is used (and similarly for INIT
, END
, etc).
get_all_symbols $type_filter
Returns a hashref, keyed by the variable names in the package. If $type_filter
is passed, the hash will contain every variable of that type in the package as values, otherwise, it will contain the typeglobs corresponding to the variable names (basically, a clone of the stash).
BUGS / CAVEATS
GLOB and FORMAT variables are not (yet) accessible through this module.
Also, see the BUGS section for the specific backends (Package::Stash::XS and Package::Stash::PP)
Please report any bugs through RT: email bug-package-stash at rt.cpan.org
, or browse to http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Package-Stash.
SUPPORT
You can find this documentation for this module with the perldoc command.
perldoc Package::Stash
You can also look for information at:
AnnoCPAN: Annotated CPAN documentation
CPAN Ratings
RT: CPAN's request tracker
Search CPAN
AUTHOR
Jesse Luehrs <doy at tozt dot net>
Based on code from Class::MOP::Package, by Stevan Little and the Moose Cabal.
SEE ALSO
-
This module is a factoring out of code that used to live here
COPYRIGHT AND LICENSE
This software is copyright (c) 2011 by Jesse Luehrs.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.