Brethren,

I have a HoH structure—actually a mix of hashes and arrays. It's created by reading an XML file, using XML::Simple. If I bless the interior hashes, am I going to mess up:

In more detail:
So a typical InspectionData structure read in from the XML looks something like 
HASH(0xb82b64)
   'InspectionRecord' => ARRAY(0xc207f0)
      0  HASH(0xb82be8)
         'FileRecord' => ARRAY(0xc20790)
            0  HASH(0xb82d08)
               'filename' => 'yelloJello.pl'
         'Inspector' => ARRAY(0xc3cfc8)
            0  HASH(0xb82c84)
               'user' => 'smith_j'
         'date' => '12-AUG-2007'
   'fdnum' => 'D0000'

[download]
If I bless the interior hashes that represent InspectionData, FileRecord and Inspector into their own classes, would/should that give indigestion to the XMLout routine? Would it represent a sin against Object Oriented design or otherwise be a venial sin?

XML::Simple stores attributes as hash references and child entities as array references (if you've used the recommended 'ForceArray' option, which I have.) There are a couple places in my code where I walk the key/value pairs of each HoH, testing to see if the value is an arrayref or a hashref: 

    my $type = ref $hohref;
    if(not $type){
    ....}
    elsif($type eq 'ARRAY'){
    ....}
    elsif($type eq 'HASH'){
        ....}
    else{
        ....}

[download]
If I understand rightly, once I've blessed the InspectionRecord etc. $type isn't going to get set to HASH anymore - it's going to come back as InspectionRecord. The code that does this test isn't specific to the Inspection project; it's supposed to be general to anything read in by XML::Simple. So I'm reluctant to added tests there to see if $type is a InspectionRecord, FileRecord, Inspector...

What I want to test for is like Is the underlying implementation of this blessed thing a hashref? This seems contrary to OO principals, but I need to do it to keep the existing code running—and, I suspect, to dump back out to XML.

Am I going about this the right way?

In summary, Randall Schwartz said

The bless operation puts a little post-it note on the hash data structure (not the reference!) that says ``I belong to Widget''.
How do I keep from choking on the post-it note?

throop

In reply to Blessing interior hashes by throop

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