Re^2: array of hash

perhaps I didn't fully understand your comment but i changed my program based on use strict. I still have problem

If I don't use the hash ref, I get this error Can't use string ("CD") as a HASH ref while "strict refs" in use at ./test.pl line 15.

and if i use hash ref, I don't get any value for the key CD Don't know why?! curr CD AB 1 currhash CD AB 1

The desired output is curr CD 0 AB 1 currhash CD 0 AB 0

#!/usr/bin/perl
 use strict;

sub parseFiles{
   my @currArr=();
my %curr;
my %tmp = $_[0];

    push @currArr,'+1';
    push @currArr,'u';
    push @currArr,%tmp; # push @currArr,%currHash; in the first case

    $curr{"my"}=[@currArr];

    $curr{"my"}->[2]{"AB"}++;

    #print scalar(keys %{$curr{"my"}->[2]}), "\n";

    #print  $curr{"my"}->[0], " ", $curr{"my"}->[1], "\n";

print "curr\n";

    foreach (keys %{$curr{"my"}->[2]}){
            print  $_, " ", $curr{"my"}->[2]{$_}, " ";
    }
    print "\n";

print "currhash\n";

    foreach (keys %tmp){
            print $_, " ", $tmp{$_}, " ";
    }
    print "\n";
}
 
sub storeHash{
my %currHash;

        $currHash{"AB"}=$currHash{"CD"}= 0;
    return %currHash;
}

sub main{
my %currHash;
    %currHash=storeHash();
    parseFiles(%currHash);
}

main();
[download]

Comment on Re^2: array of hash Download Code

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Re^3: array of hash by choroba (Cardinal) on May 27, 2014 at 11:00 UTC
`Can't use string ("CD") as a HASH ref while "strict refs" in use` [download] Yes, that's the point you perhaps didn't fully understand. `$cur{my}[2]` is `"CD"`, you can't dereference it as a hash under strict. Without strict, it's understood as symbol reference and the hash `%CD` is used, as I demonstrated in my original reply. لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ	[reply] [d/l] [select]
Re^4: array of hash by carolw (Sexton) on May 27, 2014 at 11:18 UTC
if I add your line to my program, I get the following error print Dumper $curr{my}[2], $curr{my}[2]{AB}, \%CD; Global symbol "%CD" requires explicit package name at ./test.pl line 14. In addition, how do you print the elements of $curr when using use strict? `foreach (keys %{$curr{"my"}->[2]}){ print $_, " ", $curr{"my"}->[2]{$_}, " "; } print "\n";` [download]	[reply] [d/l]
Re^5: array of hash by choroba (Cardinal) on May 27, 2014 at 11:26 UTC
First, you have to `use Data::Dumper;` [download] to be able to use `Dumper`. Second, `%CD` is created only without strict. لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ	[reply] [d/l] [select]
Re^4: array of hash by carolw (Sexton) on May 27, 2014 at 11:45 UTC
it's seems that I can access $curr{"my"}->2{"AB"} correctly but not for CD as the key when using strict. Why? Do you have the solution how to build and access the array of hash correclty? I get more and more confused	[reply]
Re^5: array of hash by choroba (Cardinal) on May 27, 2014 at 12:28 UTC
It's simple. `$curr{my}[2] = 'CD';` [download] There's no hash under 2, only a string. So you can't access a hash. The solution is to build the structure correctly. لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ	[reply] [d/l]
Re^4: array of hash by carolw (Sexton) on May 27, 2014 at 12:37 UTC
I don't want to build. I already build %currHash and then, want to assign the whole %currHash to the 3rd array element of %curr. Then, I will change the value of the keys of the hash which is the 3rd element of array of %curr but I don't want that %currHash gets changed If I do such assignment, how come that the value of the CD doesn't exist when assigning %currHash or %tmp?	[reply]
Re^5: array of hash by choroba (Cardinal) on May 27, 2014 at 12:42 UTC
You have to change the way you build the structure, because it's the source of the problem. Please read all the comments and linked pages again to understand. `push @currArr, %currHash;` [download] This line does not insert a hash into an array. It flattens the hash to a list to be inserted. Use Data::Dumper to visualize the resulting structures. What structure do you exactly want to build? If you want to create a copy of a shallow hash, use `push @currArr, { %currHash };` [download] To create a deep copy, see Clone or Storable. لսႽ† ᥲᥒ⚪⟊Ⴙᘓᖇ Ꮅᘓᖇ⎱ Ⴙᥲ𝇋ƙᘓᖇ	[reply] [d/l] [select]
Re^4: array of hash by carolw (Sexton) on May 27, 2014 at 12:31 UTC
Also how to access the value of CD using strict?	[reply]
Re^4: array of hash by carolw (Sexton) on May 27, 2014 at 12:51 UTC
I have no idea. push @currArr,%currHash doesn't seem to be correct and can't think of any thing else. I just want to build an array of hash; that is, the 3rd el of @currArr is %currHash	[reply]