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Devel::Symdump(3)     User Contributed Perl Documentation    Devel::Symdump(3)

NAME
       Devel::Symdump -	dump symbol names or the symbol	table

SYNOPSIS
	   # Constructor
	   require Devel::Symdump;
	   @packs = qw(some_package another_package);
	   $obj	= Devel::Symdump->new(@packs);	      #	no recursion
	   $obj	= Devel::Symdump->rnew(@packs);	      #	with recursion

	   # Methods
	   @array = $obj->packages;
	   @array = $obj->scalars;
	   @array = $obj->arrays;
	   @array = $obj->hashes;
	   @array = $obj->functions;
	   @array = $obj->filehandles;	# deprecated, use ios instead
	   @array = $obj->dirhandles;	# deprecated, use ios instead
	   @array = $obj->ios;
	   @array = $obj->unknowns;	# only perl version < 5.003 had	some

	   $string = $obj->as_string;
	   $string = $obj->as_HTML;
	   $string = $obj1->diff($obj2);

	   $string = Devel::Symdump->isa_tree;	  # or $obj->isa_tree
	   $string = Devel::Symdump->inh_tree;	  # or $obj->inh_tree

	   # Methods with autogenerated	objects
	   # all of those call new(@packs) internally
	   @array = Devel::Symdump->packages(@packs);
	   @array = Devel::Symdump->scalars(@packs);
	   @array = Devel::Symdump->arrays(@packs);
	   @array = Devel::Symdump->hashes(@packs);
	   @array = Devel::Symdump->functions(@packs);
	   @array = Devel::Symdump->ios(@packs);
	   @array = Devel::Symdump->unknowns(@packs);

DESCRIPTION
       This little package serves to access the	symbol table of	perl.

       "Devel::Symdump->rnew(@packages)"
	   returns a symbol table object for all subtrees below	@packages.
	   Nested Modules are analyzed recursively. If no package is given as
	   argument, it	defaults to "main". That means to get the whole	symbol
	   table, just do a "rnew" without arguments.

	   The global variable $Devel::Symdump::MAX_RECURSION limits the
	   recursion to	prevent	contention. The	default	value is set to	97,
	   just	low enough to survive the test suite without a warning about
	   deep	recursion.

       "Devel::Symdump->new(@packages)"
	   does	not go into recursion and only analyzes	the packages that are
	   given as arguments.

       packages, scalars, arrays, hashes, functions, ios
	   The methods packages(), scalars(), arrays(),	hashes(), functions(),
	   ios(), and (for older perls)	unknowns() each	return an array	of
	   fully qualified symbols of the specified type in all	packages that
	   are held within a Devel::Symdump object, but	without	the leading
	   "$",	"@" or "%". In a scalar	context, they will return the number
	   of such symbols. Unknown symbols are	usually	either formats or
	   variables that haven't yet got a defined value.

	   Note	that scalar symbol table entries are a special case.  If a
	   symbol table	entry exists at	all, presence of a scalar is currently
	   unknowable, due to a	feature	of Perl	described in "Making
	   References" in perlref point	7.  For	example, this package will
	   mark	a scalar value $foo as present if any of @foo, %foo, &foo etc.
	   have	been declared or used.

       as_string
       as_HTML
	   As_string() and as_HTML() return a simple string/HTML
	   representations of the object.

       diff
	   Diff() prints the difference	between	two Devel::Symdump objects in
	   human readable form.	The format is similar to the one used by the
	   as_string method.

       isa_tree
       inh_tree
	   Isa_tree() and inh_tree() both return a simple string
	   representation of the current inheritance tree. The difference
	   between the two methods is the direction from which the tree	is
	   viewed: top-down or bottom-up. As I'm sure, many users will have
	   different expectation about what is top and what is bottom, I'll
	   provide an example what happens when	the Socket module is loaded:

       % print Devel::Symdump->inh_tree
	       AutoLoader
		       DynaLoader
			       Socket
	       DynaLoader
		       Socket
	       Exporter
		       Carp
		       Config
		       Socket

	   The inh_tree	method shows on	the left hand side a package name and
	   indented to the right the packages that use the former.

       % print Devel::Symdump->isa_tree
	       Carp
		       Exporter
	       Config
		       Exporter
	       DynaLoader
		       AutoLoader
	       Socket
		       Exporter
		       DynaLoader
			       AutoLoader

	   The isa_tree	method displays	from left to right ISA relationships,
	   so Socket IS	A DynaLoader and DynaLoader IS A AutoLoader.
	   (Actually, they were	at the time this manpage was written)

       You may call both methods, isa_tree() and inh_tree(), with an object.
       If you do that, the object will store the output	and retrieve it	when
       you call	the same method	again later. The typical usage would be	to use
       them as class methods directly though.

SUBCLASSING
       The design of this package is intentionally primitive and allows	it to
       be subclassed easily. An	example	of a (maybe) useful subclass is
       Devel::Symdump::Export, a package which exports all methods of the
       Devel::Symdump package and turns	them into functions.

SEE ALSO
       Routines	for manipulating stashes: "Package::Stash"; to work with
       lexicals: "PadWalker".

AUTHORS
       Andreas Koenig _andk@cpan.org_ and Tom Christiansen _tchrist@perl.com_.
       Based on	the old	dumpvar.pl by Larry Wall.

COPYRIGHT, LICENSE
       This module is

       Copyright (c) 1995, 1997, 2000, 2002, 2005, 2006	Andreas	Koenig
       "<andk@cpan.org>".

       All rights reserved.

       This library is free software; you may use, redistribute	and/or modify
       it under	the same terms as Perl itself.

perl v5.24.1			  2017-02-06		     Devel::Symdump(3)

NAME | SYNOPSIS | DESCRIPTION | SUBCLASSING | SEE ALSO | AUTHORS | COPYRIGHT, LICENSE

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