Devel::ArgNames(3) Figure out the names of variables passed into subroutines.


use Devel::ArgNames;
sub foo {
warn "foo() called with arguments: "
. join(", ", map { defined() ? $_ : "<unknown>" } arg_names(@_) );
foo($bar, $gorch, $blah[4]);


When print-debugging code, you will often ind yourself going:

        print "\$foo is $foo, \$bar is $bar"

With this module, you can write a reusable subroutine easily:

        sub my_print_vars {
                my %vars;
                @vars{arg_names()} = @_;
                foreach my $var ( keys %vars ) {
                        warn "$var is $vars{$var}\n";
        my_print_vars($foo, $bar);

This module doesn't provide dumping facilities because there are too many to choose from. This is a DIY kit ;-)


arg_names [ $level ]
This function will return the names associated with the variables found on @_, at the level $level. If $level is not provided "arg_names"'s caller's caller will be used ("$level == 2" in that case).


This module is maintained using Darcs. You can get the latest version from <>, and use "darcs send" to commit changes.


Ran Eilam

Yuval Kogman <[email protected]>


        Copyright (c) 2007 Yuval Kogman. All rights reserved
        This program is free software; you can redistribute
        it and/or modify it under the same terms as Perl itself.