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in reply to Re: Sorting hash keys according to different criteria
in thread Sorting hash keys according to different criteria

Hi, Can I ask why this only prints one item in the hash array? 
my %people;
%people =(
          {
            name => "fred",
            age  => 31,
          },
          {
            name => "bill",
            age  => 32,
          });

my $length = keys %people ;
print "$length\n";

foreach my $key (sort keys %people)
{
 print("$people{$key}{'name'}: $people{$key}{'age'}\n");
}

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Code tags - dvergin 2003-06-24

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Re: Re: Re: Sorting hash keys according to different criteria
by George_Sherston (Vicar) on Jun 24, 2003 at 21:46 UTC
    It's because you've mixed up a hash of hashes with an array of hashes. %people is clearly a hash; but the thing after the = is an array of two hashes. But since, in Perl, hashes are a special kind of array, Perl just took you at your word that you wanted to treat this array as a hash.

    The end result is, %people is a hash with one key-value pair: the key is { name => "fred", age => 31, } and the value is { name => "bill", age => 32, }! I know that's not what you wanted, but it's what you told Perl to do!

    You'd get the output you want with 
    my @people = (
    {
        name => "fred",
        age => 31,
    },
    {
        name => "bill",
        age => 32,
    }
);

for (@people) {
    print "$_->{'name'}: $_->{'age'}\n";
}

    [download]
    By the way, to make your posts easier to read, you can enclose your code with <code> tags!

    § George Sherston
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