Perl 5.8 to 5.16 and HASH error

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

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Re: Perl 5.8 to 5.16 and HASH error by toolic (Bishop) on Sep 10, 2012 at 19:10 UTC
Tips from the Basic debugging checklist: diagnostics to get more info about that warning message. `use Data::Dumper; warn Dumper($Xml->{data});` to get a clearer picture of your data structure.	[reply] [d/l]
Re^2: Perl 5.8 to 5.16 and HASH error by robsgoingmad (Initiate) on Sep 12, 2012 at 07:50 UTC
Hi This is the content of the $XML structure Read more... (4 kB) Regards Rob	[reply] [d/l]
Re^3: Perl 5.8 to 5.16 and HASH error by toolic (Bishop) on Sep 12, 2012 at 12:23 UTC
`$VAR1 = { 'Table' => 'siclonesites', 'Site' => 'admin_eventres', 'Pwd' => 'woev1', 'e21' => 'siclone', 'Action' => 'Update', 'data' => [ { 'SCSS' => {},` [download] The data key is an array of hashes. See perldsc.	[reply] [d/l]
Re^4: Perl 5.8 to 5.16 and HASH error by robsgoingmad (Initiate) on Sep 14, 2012 at 18:12 UTC
Re: Perl 5.8 to 5.16 and HASH error by AnomalousMonk (Archbishop) on Sep 10, 2012 at 20:03 UTC
`foreach $key (keys %{$Xml->{data}}){ ... }` [download] In the quoted code, `$Xml` is used as a hash reference. Further in your post, you say `$Xml->[data]` contains a number of xml tags and data values. Note the difference: curly versus square braces. (I am assuming you meant to write `$Xml->[data]` in a code block because as it stands, it renders as a dead `<a>` link.) So which is it: a hash reference (curly braces) ofor an array reference (square braces)?	[reply] [d/l] [select]
Re^2: Perl 5.8 to 5.16 and HASH error by robsgoingmad (Initiate) on Sep 12, 2012 at 08:13 UTC
Hi Below is the data from $Xml using Dumper. I am not expecting to change any code. Code has moved from an old server to new server. Only differences are Linux version has changed from 2.6.24 to 2.6.18 and perl version has changed from 5.8.8 to 5.16.0 At this point I am expecting all the code to remain as it is. It has been working for years. If you advise that "things have changed" then I will need to reconsider. Read more... (4 kB) I tried the code change you suggested and received a 500 Internal Server Error. Hope the above information helps Regards Rob	[reply] [d/l]
Re: Perl 5.8 to 5.16 and HASH error by ig (Vicar) on Sep 10, 2012 at 23:52 UTC
When I am dealing with non-trivial data structures and when variables seem not to have the values I expect or need, I often use Data::Dumper to print the variables and see what I am dealing with. I might print to a log file but often find it sufficient to terminate the program with something like: use Data::Dumper; ... die Dumper($Xml); foreach $key (keys %{$Xml->{data}}){ $sql1.="`$key`,";$sql2.="`$key`=?,";$sql3.='?,'; } [download] You know that either $Xml or $Xml->{data} is not a hash reference, from the error message. I would first want to know what it is. Then I would decide whether to change the preceding code to set it to what the following code requires, or change the following code to handle what it is.	[reply] [d/l]
Re^2: Perl 5.8 to 5.16 and HASH error by robsgoingmad (Initiate) on Sep 12, 2012 at 08:15 UTC
Hi Dumper data below. Hope it helps Read more... (4 kB) Thanks for your help Rob	[reply] [d/l]
Re^3: Perl 5.8 to 5.16 and HASH error by ig (Vicar) on Sep 12, 2012 at 20:00 UTC
From your Dumper output you can see that `$Xml->{data}` is a reference to an array, not a hash. You can either change your code to produce the hash reference as it did before or change your code to work with the array as you are getting now. Which will be easier for you I can't say, having seen so little of your code. I would look carefully to see why the second hash in the array appears: the one with a single key 'XxX'. That key looks a little odd to me. Perhaps someone added some 'test' data to the input? One option would be to ignore the second and any other hashes that might appear in the array and process only the first one. This would be an easy next step at least, and you could always make further changes later. To process the first hash, you can change your loop to something like: foreach $key (keys %{$Xml->{data}->[0]}){ $sql1.="`$key`,";$sql2.="`$key`=?,";$sql3.='?,'; } [download]	[reply] [d/l] [select]
Re^4: Perl 5.8 to 5.16 and HASH error by robsgoingmad (Initiate) on Sep 14, 2012 at 18:15 UTC
Re: Perl 5.8 to 5.16 and HASH error (mod) by tye (Sage) on Sep 10, 2012 at 19:35 UTC
I'd start looking at the module version upgrade before the Perl version upgrade to explain the problem you seem to be having. - tye	[reply]
Re^2: Perl 5.8 to 5.16 and HASH error (mod) by robsgoingmad (Initiate) on Sep 12, 2012 at 08:04 UTC
Hi Not sure what you mean regarding module version upgrade. 1. Old server running Linux 2.6.24 GNU/Linux. New server running Linux 2.6.18 GBU/Linux 2. Old perl version 5.8.8, new perl version 5.16.0 I have used cpanm to upgrade all "use libraries" to latest versions. 3. The code has been copied from the old server to the new server. I am not expecting to change any of the code. Surely the same code should work? If you advise that there are differences in how code functions between the 2 different perl versions then I have a big problem. This is the first phase of transferring code from the old server. There are bigger applications to move once this is working. Thanks for your help Regards Rob	[reply]
Re^3: Perl 5.8 to 5.16 and HASH error (mod) by tye (Sage) on Sep 12, 2012 at 08:18 UTC
In your original node, you only actual show a couple of modules being used: `use strict; use XML::Simpl�e;` [download] I wasn't thinking the problem was due to strict.pm changes. I believe the data structure that is no longer in the same shape that it used to be in is one being generated by that other module. You might want to compare the version numbers of that module and even read the Changes file for that module. - tye	[reply] [d/l]
Re^4: Perl 5.8 to 5.16 and HASH error (mod) by robsgoingmad (Initiate) on Sep 14, 2012 at 18:09 UTC
Re^3: Perl 5.8 to 5.16 and HASH error (mod) by Anonymous Monk on Sep 12, 2012 at 08:21 UTC
Not sure what you mean regarding module version upgrade. He means, before upgrading perl (from 5.8.8), upgrade the modules in the old perl ( INSTALL_BASE ) That ought to break some things and perl version won't be the reason After you've fixed it to work with latest modules under 5.8.8, then upgrade to 5.16 to see what else breaks	[reply]
Re^4: Perl 5.8 to 5.16 and HASH error (mod) by robsgoingmad (Initiate) on Sep 14, 2012 at 18:11 UTC


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