strange hash thing going on

dpath2o has asked for the wisdom of the Perl Monks concerning the following question:

Does anybody know why this code is not behaving like it should

my @types0  = qw(    i    i    m    i    m    m    m    i    m    i );
my @types1  = qw(    i    i    i    i    m    m    m    i    m    i );
my @types2  = qw(    i    i    i    i    m    m    i    i    m    i );
my @types3  = qw(    i    i    i    i    m    i    i    i    m    i );
my @types4  = qw(    i    i    i    i    m    i    m    i    m    i );
my @types5  = qw(    i    i    i    i    m    m    m    i    m    i );
my @types6  = qw(    i    i    i    i    i    m    m    i    m    i );
my @types7  = qw(    i    i    i    i    m    m    m    i    m    i );
my @types8  = qw(    i    i    i    i    m    i    m    i    m    i );
my @types9  = qw(    i    i    i    i    m    m    m    i    m    i );
my @types10 = qw(    i    i    i    m    m    m    m    i    m    i );
my @types11 = qw(    i    i    m    m    m    m    m    i    m    i );
my @types12 = qw(    i    i    m    m    m    m    m    i    i    i );
my @types13 = qw(    i    i    m    m    m    m    m    i    m    i );
my @types14 = qw(    i    i    m    m    m    m    m    i    i    i );
my %changes = ( "2006_01_01_00_00_00" => @types0,
            "2006_02_03_19_00_00" => @types1,
            "2006_03_03_09_00_00" => @types2,
            "2006_04_14_22_00_00" => @types3,
            "2006_07_07_22_00_00" => @types4,
            "2006_07_20_19_00_00" => @types5,
            "2006_08_10_20_00_00" => @types6,
            "2006_10_17_21_00_00" => @types7,
            "2006_11_06_23_00_00" => @types8,
            "2006_11_27_20_00_00" => @types9,
            "2006_12_18_21_00_00" => @types10,
            "2007_03_19_20_00_00" => @types11,
            "2007_05_09_20_00_00" => @types12,
            "2007_08_06_16_00_00" => @types13,
            "2007_09_09_08_00_00" => @types14,
            );
foreach my $l1 (sort keys %changes) { print "$l1\n"; }
[download]

This is what I get when I run this above code:
2006_01_01_00_00_00
2006_03_03_09_00_00
2006_07_07_22_00_00
2006_08_10_20_00_00
2006_11_06_23_00_00
2006_12_18_21_00_00
2007_05_09_20_00_00
2007_09_09_08_00_00
i
m

Obviously somethings wrong ... Any help oh great monastery of perl wisdom?

Comment on strange hash thing going on Download Code

Replies are listed 'Best First'.
Re: strange hash thing going on by friedo (Prior) on Feb 07, 2008 at 00:34 UTC
Your `@types` arrays are getting flattened to lists in the declaration of your `%changes` hash, causing every other element in them to become a key. So your hash declaration really evaluates to `my %changes = ( "2006_01_01_00_00_00" => 'i', 'i', 'm', ...` and so on. (Since every item in your `@types` arrays is either 'i' or 'm', those keys keep clobbering themselves.) What you want is a hash of arrays, which you can make easily enough by taking a reference to the arrays: my %changes = ( "2006_01_01_00_00_00" => \@types0, "2006_02_03_19_00_00" => \@types1, "2006_03_03_09_00_00" => \@types2, "2006_04_14_22_00_00" => \@types3, "2006_07_07_22_00_00" => \@types4, "2006_07_20_19_00_00" => \@types5, "2006_08_10_20_00_00" => \@types6, "2006_10_17_21_00_00" => \@types7, "2006_11_06_23_00_00" => \@types8, "2006_11_27_20_00_00" => \@types9, "2006_12_18_21_00_00" => \@types10, "2007_03_19_20_00_00" => \@types11, "2007_05_09_20_00_00" => \@types12, "2007_08_06_16_00_00" => \@types13, "2007_09_09_08_00_00" => \@types14, ); [download]	[reply] [d/l] [select]
Re^2: strange hash thing going on by dpath2o (Acolyte) on Feb 07, 2008 at 00:38 UTC
Friedo, You're a beautiful golden God of love ... Thank You!	[reply]
Re: strange hash thing going on by Cody Pendant (Prior) on Feb 07, 2008 at 03:36 UTC
Just because someone's got to say it -- when you find yourself doing "Thing_n = 'foo', Thing_n+1 = 'bar', Thing_n+2 = 'baz'" you should hear a voice whispering in your ear "use an array!". Nobody says perl looks like line-noise any more kids today don't know what line-noise IS ...	[reply]