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



NAME
       Devel::Dwarn - return Dwarn @return_value

SYNOPSIS
         use Devel::Dwarn;

         return Dwarn some_call(...)

       is equivalent to:

         use Data::Dumper::Concise;

         if (wantarray) {
            my @return = some_call(...);
            warn Dumper(@return);
            return @return;
         } else {
            my $return = some_call(...);
            warn Dumper($return);
            return $return;
         }

       but shorter. If you need to force scalar context on the value,

         use Devel::Dwarn;

         return DwarnS some_call(...)

       is equivalent to:

         use Data::Dumper::Concise;

         my $return = some_call(...);
         warn Dumper($return);
         return $return;

       If you need to force list context on the value,

         use Devel::Dwarn;

         return DwarnL some_call(...)

       is equivalent to:

         use Data::Dumper::Concise;

         my @return = some_call(...);
         warn Dumper(@return);
         return @return;

       If you want to label your output, try DwarnN

         use Devel::Dwarn;

         return DwarnN $foo

       is equivalent to:

         use Data::Dumper::Concise;

         my @return = some_call(...);
         warn '$foo => ' . Dumper(@return);
         return @return;

       If you want to output a reference returned by a method easily, try $Dwarn

        $foo->bar->{baz}->$Dwarn

       is equivalent to:

         my $return = $foo->bar->{baz};
         warn Dumper($return);
         return $return;

       If you want to immediately die after outputting the data structure, every Dwarn subroutine has a
       paired Ddie version, so just replace the warn with die.  For example:

        DdieL 'foo', { bar => 'baz' };

TIPS AND TRICKS
   global usage
       Instead of always just doing:

         use Devel::Dwarn;

         Dwarn ...

       We tend to do:

         perl -MDevel::Dwarn foo.pl

       (and then in the perl code:)

         ::Dwarn ...

       That way, if you leave them in and run without the "use Devel::Dwarn" the program will fail to
       compile and you are less likely to check it in by accident.  Furthmore it allows that much less
       friction to add debug messages.

   method chaining
       One trick which is useful when doing method chaining is the following:

         my $foo = Bar->new;
         $foo->bar->baz->Devel::Dwarn::DwarnS->biff;

       which is the same as:

         my $foo = Bar->new;
         (DwarnS $foo->bar->baz)->biff;

SEE ALSO
       This module is really just a shortcut for Data::Dumper::Concise::Sugar, check it out for more
       complete documentation.



perl v5.16.2                                     2011-01-20                                  Devel::Dwarn(3)