Assuming the code like this: 

use Data::Dumper;
my $hashref={
  ...., 
  k1 => { 
    ....
    k2 => {
      ....
      kN => {...., mydata => MyClass->new(), .... }}}};
print(Dumper($hashref));

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the printout will contain somewhere something like 
....
    mydata => bless(..., 'MyClass')
....

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I'm looking for a way to get $hashref pretty-printed, so that the result looks like this: 
....
    mydata => 'MyOwnRepresentation of the MyClass instance'
....

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Note that the original hash should not be changed, and I don't know at compile time, where the mydata key is buried inside the hash. I even don't know whether it's name really is 'mydata'. I only know that somewhere in the hash are some data of type MyClass, and these are the ones where I want to take control on how they are pretty printed.

My first idea was to set 

sub MyClass::myfreezer { ... }
$Data::Dumper::Freeze='myfreezer'

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and handle everythin in myfreezer, but as far I can see, a freeze function can only change the internals to the object to be frozen. Is it possible to find a way (without writing a new pretty-printer from scratch)?

I also had a look at Data::Dumper::Streamer, which seems to have a more flexible "Freeze", but still I don't see how this can be achieved.

-- 
Ronald Fischer <ynnor@mm.st>

In reply to Fine grain control over Data::Dumper by rovf

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