Re: how to include an array of hashes in a hash of hashes?

"Please advise me on how to structure my data."

I don't think there's anything wrong with your current structure, except that you need one per component=XXX with each being held in another hash whose keys are the XXX values.

Here's how I produced that:

$ perl -Mstrict -Mwarnings -e '
    use Data::Dumper;

    my @data = qw{
        component=HF
        version=NULL
        sourcefile=filename1
        sourcesum=checksumfile1
        sourcefile=filename2
        sourcesum=checksumfile2
        sourcefile=filename3
        sourcesum=checksumfile3
        component=SVM
        version=10.0.70.102
        sourcefile=filename4
        sourcesum=checksumfile4
    };

    my (%compdata, $comp, $file);

    for (@data) {
        my ($key, $value) = split /=/;

        for ($key) {
            /component/  && do { $comp = $value; last };
            /version/    && do { $compdata{$comp}{version} = $value; l
+ast };
            /sourcefile/ && do { $file = $value; last };
            /sourcesum/  && do { $compdata{$comp}{sources}{$file} = $v
+alue };
        }
    }

    print Dumper \%compdata;
'
$VAR1 = {
          'SVM' => {
                     'version' => '10.0.70.102',
                     'sources' => {
                                    'filename4' => 'checksumfile4'
                                  }
                   },
          'HF' => {
                    'version' => 'NULL',
                    'sources' => {
                                   'filename3' => 'checksumfile3',
                                   'filename2' => 'checksumfile2',
                                   'filename1' => 'checksumfile1'
                                 }
                  }
        };
[download]

-- Ken

Comment on Re: how to include an array of hashes in a hash of hashes? Select or Download Code

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Re^2: how to include an array of hashes in a hash of hashes? by anadem (Scribe) on Sep 17, 2013 at 17:42 UTC
Thanks so much for a very elegant solution! Much appreciated. (Downside is that it makes my perl code look like COBOL ;-)	[reply]
Re^2: how to include an array of hashes in a hash of hashes? by anadem (Scribe) on Sep 23, 2013 at 20:49 UTC
Please help with more syntax! I turns out that I need an array as well, to retain the order of the source files. Something like the "<<WRONG" line here: `my (%compdata, $comp, $file, @srcfiles); for (@data) { my ($key, $value) = split /=/; for ($key) { /component/ && do { $comp = $value; last }; /version/ && do { $compdata{$comp}{version} = $value; last }; /sourcefile/ && do { $file = $value; push (@($compdata{$comp}{$srcfiles}), $value); # <<WRONG last }; /sourcesum/ && do { $compdata{$comp}{sources}{$file} = $value }; } }` [download] For example, when the data is `component=HF version=NULL sourcefile=file10 sourcesum=checksum10 sourcefile=file2 sourcesum=checksum2 sourcefile=file3 sourcesum=checksum3` [download] When using only the hash, the output is `'sources' => { 'file3' => 'checksum3', 'file2' => 'checksum2', 'file10' => 'checksum10'` [download] but I need to be able to get the same order as the provided data (by using foreach @srcfiles { get hashvalue } (which is also syntax I don't know)) `'sources' => { 'file10' => 'checksum10' 'file3' => 'checksum3', 'file2' => 'checksum2',` [download]	[reply] [d/l] [select]
Re^3: how to include an array of hashes in a hash of hashes? by kcott (Archbishop) on Sep 24, 2013 at 02:17 UTC
Flagging something as "WRONG", without providing a reason, is not particularly useful. "`push @{ ARRAYREF }, LIST`" was probably the syntax you wanted; however, that says nothing about whether the logic or functionality is "RIGHT" or "WRONG", nor what those terms mean in either context. Hashes have no inherent ordering. Stating "When using only the hash, the output is ..." is meaningless. If you need to keep track of the order of hash keys, you have to do it yourself and an array is usually the best tool for this task. See keys for a discussion of this; there's a lot more detail in the Hash Algorithm section of "perlsec: Algorithmic Complexity Attacks". Before writing any more code, I'd recommend that you look at "perlreftut - Mark's very short tutorial about references", "perldsc - Perl Data Structures Cookbook" and "perllol - Manipulating Arrays of Arrays in Perl". Next consider what data you need to collect and how you're going to use it. That should provide insight into how to store and subsequently access the data. Storing the data without sufficient forethought, and then finding you have to go back to square one and start all over again, is a waste of time, effort and money (not to mention just plain, old boring). Here's a possible approach you could take: `#!/usr/bin/env perl use strict; use warnings; use autodie; use Data::Dumper; my @out; open my $in_fh, '<', 'pm_1054339_data.txt'; while (<$in_fh>) { chomp; my ($key, $value) = split /=/; for ($key) { /component/ && do { push @out, { $key => $value }; last }; /version/ && do { $out[-1]{$key} = $value; last }; /sourcefile/ && do { push @{$out[-1]{order}}, $value; last }; /sourcesum/ && do { $out[-1]{sources}{$out[-1]{order}[-1]} = +$value }; } } close $in_fh; print Dumper \@out;` [download] With this input: `$ cat pm_1054339_data.txt component=HF version=NULL sourcefile=filename1 sourcesum=checksumfile1 sourcefile=filename2 sourcesum=checksumfile2 sourcefile=filename3 sourcesum=checksumfile3 component=SVM version=10.0.70.102 sourcefile=filename4 sourcesum=checksumfile4 component=HF_2 version=NULL sourcefile=file10 sourcesum=checksum10 sourcefile=file2 sourcesum=checksum2 sourcefile=file3 sourcesum=checksum3` [download] You get this output: $ pm_1054339_data.pl $VAR1 = [ { 'order' => [ 'filename1', 'filename2', 'filename3' ], 'sources' => { 'filename3' => 'checksumfile3', 'filename1' => 'checksumfile1', 'filename2' => 'checksumfile2' }, 'version' => 'NULL', 'component' => 'HF' }, { 'version' => '10.0.70.102', 'order' => [ 'filename4' ], 'sources' => { 'filename4' => 'checksumfile4' }, 'component' => 'SVM' }, { 'version' => 'NULL', 'sources' => { 'file10' => 'checksum10', 'file3' => 'checksum3', 'file2' => 'checksum2' }, 'order' => [ 'file10', 'file2', 'file3' ], 'component' => 'HF_2' } ]; [download] -- Ken	[reply] [d/l] [select]
Re^4: how to include an array of hashes in a hash of hashes? by anadem (Scribe) on Sep 27, 2013 at 02:52 UTC
Once again I'm very grateful for your kind reply and advice. Thank you for the pointers to places for me to learn: data structures are a big hole in my Perl knowledge and I will try to get some understanding into my fossilized head. As it happens, the requirements I'm given have been changed yet again but I'll defer questions until I can visualize what's happening with this code in your reply `/component/ && do { push @out, { $key => $value }; last }; /version/ && do { $out[-1]{$key} = $value; last }; /sourcefile/ && do { push @{$out[-1]{order}}, $value; last }; /sourcesum/ && do { $out[-1]{sources}{$out[-1]{order}[-1]} =` [download] and hope then to need no more help ;-) Many thanks again Alan	[reply] [d/l]