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in reply to hash to text

So my question is how to make that output look normal(like what it's supposed to be) ?

What ARE you expecting $h{word2} to contain, [[2,3],3] or [2,3,3] ?

Does this make you any wiser or perhaps you ought to check out the docs?

#!perl -w
use strict;

my %h = (
word1 =>[2,3],
word3 =>[1,2]
);
$h{word2} = [ $h{'word1'},3],
$h{word4} = [ @{ $h{'word1'} },3],

print $h{'word2'}->[0]->[0], "\n";       # Alternative1
print @{ @{ $h{'word2'} }[0] }[0], "\n"; # Alternative1

print @{ $h{'word4'}}[0], "\n";          # Alternative2
print $h{'word4'}->[0], "\n";            # Alternative2

__OUTPUT__
2
2
2
2

[download]

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Re^2: hash to text
by chiburashka (Initiate) on Aug 14, 2004 at 21:19 UTC
    btw, why when i change the code to :
    my %h = (
word1 =>[2,3],
word2 =>[1,3],
word3 =>[1,2]
);
$h{word1} = [ $h{word2},$h{word3}];
$h{word2} = [ $h{word1},$h{word3}];
$h{word3} = [ $h{word1},$h{word2}];

print @{ @{ $h{'word3'} }[0] }[0], "\n";

    [download]

    it gives me out the output : ARRAY(0x8064e68)

    And, how can i see this in normal now ?

[reply]
[d/l]

      Let's look at your code with some hand calculations thrown in for fun. 

      #!/usr/bin/perl

my %h = (
word1 =>[2,3],
word2 =>[1,3],
word3 =>[1,2]
);
$h{word1} = [ $h{word2},$h{word3}]; # [[1,3],[1,2]]
$h{word2} = [ $h{word1},$h{word3}]; # [[[1,3],[1,2]],[1,2]]
$h{word3} = [ $h{word1},$h{word2}]; # [[[1,3],[1,2]],[[[1,3],[1,2]],[1
+,2]]]

print @{ @{ $h{'word3'} }[0] }[0], "\n";

      [download]

      If you look at the data above, you'll see that you're dereferencing the structure twice. Well, when looking at the zeroeth element, you'll notice that your print statement above gives a reference to an array, specifically [1,3].

      To print it, you will need to deref it one more time. 

      print @{ @{ $h{'word3'} }[0] }[0]->[0], "\n"; # prints "1"
print @{ @{ $h{'word3'} }[0] }[0]->[1], "\n"; # prints "3"

      [download]

      When in doubt, walk through your data by hand; use Data::Dumper; inspect things.

      Hope this helps,

      -v
      "Perl. There is no substitute."
[reply]
[d/l]
[select]
Re^2: hash to text
by chiburashka (Initiate) on Aug 14, 2004 at 20:56 UTC
    it should contain [[2,3],3].
[reply]
[d/l]

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