|Perl: the Markov chain saw|
Data::Dumper(::Simple) is your friendby cajun (Chaplain)
|on Jul 05, 2005 at 01:34 UTC ( #472337=perlmeditation: print w/replies, xml )||Need Help??|
For a long time on PM I have seen people saying "use Data::Dumper" and look at your data. When I have seen this, I've always wondered why do I need to use a module to look at my data when it is so easy to print the data without a module.
For the past couple of days I have been working on a piece of code that I just could NOT figure out why I was getting "Use of uninitialized value....". I used the snippet above several times. I wrote short scripts to prove to myself my code was working. Yet, in the actual script, the same code would not work.
My hash looked something like this:
I struggled with this for a couple of days trying to see what was going on. Why was I getting this mysterious 'undef'. I thought about using Data::Dumper as I had seen so many times here. But I didn't get around to it until today.
I put in Data::Dumper::Simple and within 2 minutes saw the issue. My data that I thought looked like the above, really looked more like this:
There was a trailing space in my keys. I would probably have never located this problem without Data::Dumper.
Data::Dumper(::Simple) is my new friend
I guess lessons learned the hard way are the ones you remember most easily.
Update: Thanks itub and Nkuvu. Both very good points. Using delimiters around the variables is an excellent idea that I will remember. Thanks.
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