I use this code a lot when I want a quick and easy removable way to look at the contents of objects of classes I'm developing, and to be able to look at other data-structures as well.

Just add the code below to your main program, and you can do the following: 

my $foo = new Foo;
$foo->dump; # dumps automatically to STDERR
print $foo->dump;  #dumps to STDOUT
print FOO $foo->dump;  # dumps to filehandle FOO

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or, if you don't have objects but want to quickly dump a data-structure: 
a->dump( $foo );   # dumps automatically to STDERR
print a->dump( $foo );  #dumps to STDOUT
print FOO a->dump( $foo ); # dumps to filehandle FOO

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I wonder whether it would make sense to make a "dump" pragma for this and upload to CPAN.

sub UNIVERSAL::dump {

# Obtain the object / class
# Make sure that we have Data::Dumper
# Return Dumper output if not in void context
# Send Dumper output to STDERR otherwise

    my $self = shift;
    require Data::Dumper;
    return Data::Dumper::Dumper( @_ ? @_ : $self ) if defined wantarra
+y;
    print STDERR Data::Dumper::Dumper( @_ ? @_ : $self );
} #UNIVERSAL::dump

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Replies are listed 'Best First'.
Re: Quick Dumper
by zentara (Cardinal) on Dec 03, 2003 at 15:44 UTC
    Just for the benefit of monks who normally don't check out all the new arrivals on cpan.....this reminds me of a new cool module which does something similar to this, it's callled Tk::Objscanner It is sort of reminiscent of ptkdb, but it will pop a Tk window with the dump of any object. It has a useful companion module Tk::ObjEditor. 
    # user code to produce data
Tk::ObjScanner::scan_object($mydata) ;
# resume user code

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Re: Quick Dumper
by diotalevi (Canon) on Dec 03, 2003 at 13:09 UTC
    Sure, as long as you don't call it a pragma. I'd expect some sort of scoping then and your code is all about being global.
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      Indeed. It's intended as a debugging tool. Ease of use is the only goal! Something that you would add as: 
      perl -Mdump yourprogram

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      and which would then allow you to call the "dump" method on your objects without any other changes to your program.

      Liz

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[d/l]

        What, just like that? I'm not sure how that would work since you'd have to have built in the ->dump method calls beforehand. Or do you include things like $obj->dump if $obj->can( 'dump' ) so it works in both cases?

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[d/l]

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