Selectively truncating data structure dumps

metaperl has asked for the wisdom of the Perl Monks concerning the following question:

I have a nested hashref. At some point in this hashref, the key tz has a hashref as its value. One key in this hashref is spans. I want this hashref to not be printed or truncated to maybe 20 characters max. How can I use Data::Dump or something else to get a dump of the whole structure but with this one key greatly reduced in output amount? The docs to Data::Dump::Filtered are opaque to me. Here's a sample of my data structure:

$VAR6 = {
    'stops' => [
        {
            'destination' => {
                'dt' => bless(
                    {
                        'local_rd_secs' => 54212,
                        'local_rd_days' => 734444,
                        'locale'        => bless(
                            {
                                'default_time_format_length' => 'mediu
+m',
                                'native_language'            => 'Engli
+sh',
                                'native_territory'           => 'Unite
+d States',
                                'native_complete_name' =>
                                  'English United States',
                                'en_language'                => 'Engli
+sh',
                                'id'                         => 'en_US
+',
                                'default_date_format_length' => 'mediu
+m',
                                'en_complete_name' => 'English United 
+States',
                                'en_territory'     => 'United States'
                            },
                            'DateTime::Locale::en_US'
                        ),
                        'rd_nanosecs' => 0,
                        'utc_rd_secs' => 68612,
                        'local_c'     => {
                            'hour'           => 15,
                            'second'         => 32,
                            'month'          => 11,
                            'quarter'        => 4,
                            'day_of_year'    => 307,
                            'day_of_quarter' => 34,
                            'minute'         => 3,
                            'day'            => 3,
                            'day_of_week'    => 4,
                            'year'           => 2011
                        },
                        'formatter' => undef,
                        'utc_year'  => 2012,
                        'tz'        => bless(
                            {
                                'last_offset' => -18000,
                                'spans'       => [
                                    [
                                        '-1.#INF',
                                        '59418032400',
                                        '-1.#INF',
                                        '59418014638',
[download]

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Re: Selectively truncating data structure dumps by Anonymous Monk on Nov 04, 2011 at 06:22 UTC
I do something like `{ local $foo->{bar}{bar}{bar} = substr $foo->{bar}{bar}{bar}, 0, 20; Dump( $foo ); }` [download]	[reply] [d/l]
Re: Selectively truncating data structure dumps by metaperl (Curate) on Nov 04, 2011 at 17:05 UTC
I found a couple of good links here: http://www.effectiveperlprogramming.com/blog/312 http://www.martin-evans.me.uk/node/113 The mantra of every experienced web application developer is the same: thou shalt separate business logic from display. Ironically, almost all template engines allow violation of this separation principle, which is the very impetus for HTML template engine development. -- Terence Parr, "Enforcing Strict Model View Separation in Template Engines"	[reply]

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