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



NAME
       Devel::PartialDump - Partial dumping of data structures, optimized for argument printing.

SYNOPSIS
               use Devel::PartialDump;

               sub foo {
                       print "foo called with args: " . Devel::PartialDump->new->dump(@_);
               }

               use Devel::PartialDump qw(warn);

               # warn is overloaded to create a concise dump instead of stringifying $some_bad_data
               warn "this made a boo boo: ", $some_bad_data

DESCRIPTION
       This module is a data dumper optimized for logging of arbitrary parameters.

       It attempts to truncate overly verbose data, in a way that is hopefully more useful for diagnostics
       warnings than

               warn Dumper(@stuff);

       Unlike other data dumping modules there are no attempts at correctness or cross referencing, this is
       only meant to provide a slightly deeper look into the data in question.

       There is a default recursion limit, and a default truncation of long lists, and the dump is formatted
       on one line (new lines in strings are escaped), to aid in readability.

       You can enable it temporarily by importing functions like "warn", "croak" etc to get more informative
       errors during development, or even use it as:

               BEGIN { local $@; eval "use Devel::PartialDump qw(...)" }

       to get DWIM formatting only if it's installed, without introducing a dependency.

SAMPLE OUTPUT
       "foo"
               "foo"

       "foo" => "bar"
               foo: "bar"

       "foo => "bar", gorch => [ 1, "bah" ]"
               foo: "bar", gorch: [ 1, "bah" ]

       "[ { foo => ["bar"] } ]"
               [ { foo: ARRAY(0x9b265d0) } ]

       "[ 1 .. 10 ]"
               [ 1, 2, 3, 4, 5, 6, ... ]

       "foo\nbar"
               "foo\nbar"

       ""foo" . chr(1)"
               "foo\x{1}"

ATTRIBUTES
       max_length
           The maximum character length of the dump.

           Anything bigger than this will be truncated.

           Not defined by default.

       max_elements
           The maximum number of elements (array elements or pairs in a hash) to print.

           Defualts to 6.

       max_depth
           The maximum level of recursion.

           Defaults to 2.

       stringify
           Whether or not to let objects stringify themeslves, instead of using "StrVal" in overload to
           avoid sideffects.

           Defaults to false (no overloading).

       pairs
           Whether or not to autodetect named args as pairs in the main "dump" function.  If this attribute
           is true, and the top level value list is even sized, and every odd element is not a reference,
           then it will dumped as pairs instead of a list.

EXPORTS
       All exports are optional, nothing is exported by default.

       This module uses Sub::Exporter, so exports can be renamed, curried, etc.

       warn
       show
       show_scalar
       croak
       carp
       confess
       cluck
       dump
           See the various methods for behavior documentation.

           These methods will use $Devel::PartialDump::default_dumper as the invocant if the first argument
           is not blessed and "isa" Devel::PartialDump, so they can be used as functions too.

           Particularly "warn" can be used as a drop in replacement for the built in warn:

                   warn "blah blah: ", $some_data;

           by importing

                   use Devel::PartialDump qw(warn);

           $some_data will be have some of it's data dumped.

       $default_dumper
           The default dumper object to use for export style calls.

           Can be assigned to to alter behavior globally.

           This is generally useful when using the "warn" export as a drop in replacement for "CORE::warn".

METHODS
       warn @blah
           A warpper for "dump" that prints strings plainly.

       show @blah
       show_scalar $x
           Like "warn", but instead of returning the value from "warn" it returns its arguments, so it can
           be used in the middle of an expression.

           Note that

                   my $x = show foo();

           will actually evaluaate "foo" in list context, so if you only want to dump a single element and
           retain scalar context use

                   my $x = show_scalar foo();

           which has a prototype of "$" (as opposed to taking a list).

           This is similar to the venerable Ingy's fabulous and amazing XXX module.

       carp
       croak
       confess
       cluck
           Drop in replacements for Carp exports, that format their arguments like "warn".

       dump @stuff
           Returns a one line, human readable, concise dump of @stuff.

           If called in void context, will "warn" with the dump.

           Truncates the dump according to "max_length" if specified.

       dump_as_list $depth, @stuff
       dump_as_pairs $depth, @stuff
           Dump @stuff using the various formatting functions.

           Dump as pairs returns comma delimited pairs with "=>" between the key and the value.

           Dump as list returns a comma delimited dump of the values.

       frmat $depth, $value
       format_key $depth, $key
       format_object $depth, $object
       format_ref $depth, $Ref
       format_array $depth, $array_ref
       format_hash $depth, $hash_ref
       format_undef $depth, undef
       format_string $depth, $string
       format_number $depth, $number
       quote $string
           The various formatting methods.

           You can override these to provide a custom format.

           "format_array" and "format_hash" recurse with "$depth + 1" into "dump_as_list" and
           "dump_as_pairs" respectively.

           "format_ref" delegates to "format_array" and "format_hash" and does the "max_depth" tracking. It
           will simply stringify the ref if the recursion limit has been reached.

VERSION CONTROL
       This module is maintained using git. You can get the latest version from
       http://github.com/rafl/devel-partialdump <http://github.com/rafl/devel-partialdump>.

AUTHOR
       Yuval Kogman <nothingmuch@woobling.org>

COPYRIGHT
               Copyright (c) 2008, 2009 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.



perl v5.16.2                                     2011-05-05                            Devel::PartialDump(3)