Perl6::Caller(3pm) User Contributed Perl Documentation Perl6::Caller(3pm)
NAME
Perl6::Caller - OO "caller()" interface
VERSION
Version 0.04
SYNOPSIS
use Perl6::Caller;
my $sub = caller->subroutine;
my $line_number = caller->line;
my $is_require = caller(3)->is_require;
EXPORT
"caller"
# standard usage
print "In ", caller->subroutine,
" called from ", caller->file,
" line ", caller->line;
# get a caller object
my $caller = caller;
my $caller = caller(); # same thing
# get a caller object for a different stack from
my $caller = caller(2); # two stack frames up
print $caller->package; # prints the package name
# enjoy the original flavor
my @caller = caller; # original caller behavior
print $caller[0], # prints the package name
DESCRIPTION
This module is experimental. It's also alpha. Bug reports and patches welcome.
By default, this module exports the "caller" function. This automatically returns a new "caller" object. An optional argument specifies
how many stack frames back to skip, just like the "CORE::caller" function. This lets you do things like this:
print "In ", caller->subroutine,
" called from ", caller->file,
" line ", caller->line;
If you do not wish the "caller" function imported, specify an empty import list and instantiate a new "Perl6::Caller" object.
use Perl6::Caller ();
my $caller = Perl6::Caller->new;
print $caller->line;
Note: if the results from the module seem strange, please read perldoc -s caller carefully. It has stranger behavior than you might be
aware.
METHODS
The following methods are available on the "caller" object. They return the same values as documented in perldoc -f caller.
There are no "hints" and "bitmask" methods because those are documented as for internal use only.
o "package"
o "filename"
o "line"
o "subroutine"
o "hasargs"
o "wantarray"
o "evaltext"
o "is_require"
Note that each of these values will report correctly for when the caller object was created. For example, the following will probably
print different line numbers:
print caller->line;
foo();
sub foo {
print caller->line;
}
However, the following will print the same line numbers:
my $caller = Perl6::Caller->new; # everything is relative to here
print $caller->line;
foo($caller);
sub foo {
my $caller = shift;
print $caller->line;
}
CAVEATS
Most of the time, this package should just work and not interfere with anything else.
o $hints, $bitmask
'hints' and 'bitmask' are not available. They are documented to be for internal use only and should not be relied upon. Further, the
bitmask caused strange test failures, so I opted not to include them.
o Subclassing
Don't.
o Perl 6
I'm not entirely comfortable with the namespace. The Perl 6 caller actually does considerably more, but for me to have a hope of
working that in, I need proper introspection and I don't have that. Thus, I've settled for simply having a caller object.
o *CORE::GLOBAL::caller
I didn't implement this, though I was tempted. It turns out to be a bit tricky in spots and I'm very concerned about globally
overriding behavior. I might change my mind in the future if there's enough demand.
o Overloading
In string context, this returns the package name. This is to support the original "caller" behavior.
o List Context
In list context, we simply default to the original behavior of "CORE::caller". However, this always assumes we've called caller with
an argument. Calling "caller" and caller(0) are identical with this module. It's difficult to avoid since the stack frame changes.
AUTHOR
Curtis "Ovid" Poe, "<ovid@cpan.org>"
ACKNOWLEDGEMENTS
Thanks to "phaylon" for helping me revisit a bad design issue with this.
BUGS
Please report any bugs or feature requests to "bug-perl6-caller@rt.cpan.org", or through the web interface at
<http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Perl6-Caller>. I will be notified, and then you'll automatically be notified of progress
on your bug as I make changes.
ACKNOWLEDGEMENTS
COPYRIGHT &; LICENSE
Copyright 2007 Curtis "Ovid" Poe, all rights reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
perl v5.10.1 2009-10-18 Perl6::Caller(3pm)