devel::caller(3) [osx man page]

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

NAME

       Devel::Caller - meatier versions of "caller"

SYNOPSIS

	use Devel::Caller qw(caller_cv);
	$foo = sub { print "huzzah
" if $foo == caller_cv(0) };
	$foo->();  # prints huzzah

	use Devel::Caller qw(called_with);
	sub foo { print called_with(0,1); }
	foo( my @foo ); # should print '@foo'

DESCRIPTION

       caller_cv($level)
	   "caller_cv" gives you the coderef of the subroutine being invoked at the call frame indicated by the value of $level

       caller_args($level)
	   Returns the arguments passed into the caller at level $level

       caller_vars( $level, $names ) =item called_with($level, $names)
	   "called_with" returns a list of references to the original arguments to the subroutine at $level.  if $names is true, the names of the
	   variables will be returned instead

	   constants are returned as "undef" in both cases

       called_as_method($level)
	   "called_as_method" returns true if the subroutine at $level was called as a method.

BUGS

       All of these routines are susceptible to the same limitations as "caller" as described in "caller" in perlfunc

       The deparsing of the optree perfomed by called_with is fairly simple-minded and so a bit flaky.

       o   As a version 2.0 of Devel::Caller we no longer maintain compatibility with versions of perl earlier than 5.8.2.  Older versions
	   continue to be available from CPAN and backpan.

SEE ALSO

       "caller" in perlfunc, PadWalker, Devel::Peek

AUTHOR

       Richard Clamp <richardc@unixbeard.net> with close reference to PadWalker by Robin Houston

COPYRIGHT

       Copyright (c) 2002, 2003, 2006, 2007, 2008, 2010 Richard Clamp. All Rights Reserved.  This module is free software. It may be used,
       redistributed and/or modified under the same terms as Perl itself.

POD ERRORS

       Hey! The above document had some coding errors, which are explained below:

       Around line 214:
	   You forgot a '=back' before '=head1'

perl v5.16.2							    2010-04-08							  Devel::Caller(3)

PadWalker(3)						User Contributed Perl Documentation					      PadWalker(3)

NAME

       PadWalker - play with other peoples' lexical variables

SYNOPSIS

	 use PadWalker qw(peek_my peek_our peek_sub closed_over);
	 ...

DESCRIPTION

       PadWalker is a module which allows you to inspect (and even change!)  lexical variables in any subroutine which called you. It will only
       show those variables which are in scope at the point of the call.

       PadWalker is particularly useful for debugging. It's even used by Perl's built-in debugger. (It can also be used for evil, of course.)

       I wouldn't recommend using PadWalker directly in production code, but it's your call. Some of the modules that use PadWalker internally are
       certainly safe for and useful in production.

       peek_my LEVEL
       peek_our LEVEL
	   The LEVEL argument is interpreted just like the argument to "caller".  So peek_my(0) returns a reference to a hash of all the "my"
	   variables that are currently in scope; peek_my(1) returns a reference to a hash of all the "my" variables that are in scope at the
	   point where the current sub was called, and so on.

	   "peek_our" works in the same way, except that it lists the "our" variables rather than the "my" variables.

	   The hash associates each variable name with a reference to its value. The variable names include the sigil, so the variable $x is
	   represented by the string '$x'.

	   For example:

	     my $x = 12;
	     my $h = peek_my (0);
	     ${$h->{'$x'}}++;

	     print $x;	# prints 13

	   Or a more complex example:

	     sub increment_my_x {
	       my $h = peek_my (1);
	       ${$h->{'$x'}}++;
	     }

	     my $x=5;
	     increment_my_x;
	     print $x;	# prints 6

       peek_sub SUB
	   The "peek_sub" routine takes a coderef as its argument, and returns a hash of the "my" variables used in that sub. The values will
	   usually be undefined unless the sub is in use (i.e. in the call-chain) at the time. On the other hand:

	     my $x = "Hello!";
	     my $r = peek_sub(sub {$x})->{'$x'};
	     print "$$r
";	   # prints 'Hello!'

	   If the sub defines several "my" variables with the same name, you'll get the last one. I don't know of any use for "peek_sub" that
	   isn't broken as a result of this, and it will probably be deprecated in a future version in favour of some alternative interface.

       closed_over SUB
	   "closed_over" is similar to "peek_sub", except that it only lists the "my" variables which are used in the subroutine but defined
	   outside: in other words, the variables which it closes over. This does have reasonable uses: see Data::Dump::Streamer, for example (a
	   future version of which may in fact use "closed_over").

       set_closed_over SUB, HASH_REF
	   "set_closed_over" reassigns the pad variables that are closed over by the subroutine.

	   The second argument is a hash of references, much like the one returned from "closed_over".

       var_name LEVEL, VAR_REF
       var_name SUB,   VAR_REF
	   "var_name(sub, var_ref)" returns the name of the variable referred to by "var_ref", provided it is a "my" variable used in the sub. The
	   "sub" parameter can be either a CODE reference or a number. If it's a number, it's treated the same way as the argument to "peek_my".

	   For example,

	     my $foo;
	     print var_name(0, $foo);	  # prints '$foo'

	     sub my_name {
	       return var_name(1, shift);
	     }
	     print my_name($foo);	  # ditto

AUTHOR

       Robin Houston <robin@cpan.org>

       With contributions from Richard Soberberg, Jesse Luehrs and Yuval Kogman, bug-spotting from Peter Scott, Dave Mitchell and Goro Fuji, and
       suggestions from demerphq.

SEE ALSO

       Devel::LexAlias, Devel::Caller, Sub::Parameters

COPYRIGHT

       Copyright (c) 2000-2009, Robin Houston. All Rights Reserved.  This module is free software. It may be used, redistributed and/or modified
       under the same terms as Perl itself.

perl v5.16.3							    2012-08-24							      PadWalker(3)