Updated: minor code changes and test harness added. 
sub deep_search {
  my $target = shift;
  my $test = shift;
  
  # Avoid infinite loops by maintaining map of objects encountered
  local %SearchCache = ( undef => undef ) unless ( exists $SearchCache
+{undef} );
  return if ( $SearchCache{ $target } ++ );
  
  # Determine data type of unblessed reference or blessed object
  my $ref = ref( $target );
  if ( "$target" =~ /^\Q$ref\E\=([A-Z]+)\(0x[0-9a-f]+\)$/ ) { $ref = $
+1 }
  
  ( $test->( $target ) ? $target : () ), 
  ( map { deep_search($_, $test) } grep { ref($_) } (
    ($ref eq 'HASH') ? values %$target :
    ($ref eq 'ARRAY') ? @$target :
    ($ref eq 'REF' or $ref eq 'SCALAR') ? $$target : ()
  ) )
}

my $struct = {
  foo => bless( [ 0, 1, 2 ], 'Foo' ),
  bar => bless( [ 3, 4, 5 ], 'Bar' ),
  foozles => [
    { foolish => bless( [ 6, 7, 8 ], 'Foo' ), }
  ],
};

print join '', map "$_\n", deep_search( $struct, sub { ref( $_[0] ) eq
+ 'Foo' } )

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In reply to Re: searching for an object reference by simonm
in thread searching for an object reference by Anonymous Monk

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