Re: Accessing the hash name in perl

As hippo said, your code goes about your task in an over-complicated way. Just load the library normally and call a function in it. ( See the monastery's Tutorials on modules. )

MyLib.pm :

package MyLib;
use strict; use warnings;

sub get_data {
    my %hash = (
        A => {
            a => 1,
            b => 2,
        },
        B => {
            a => 3,
            b => 4,
        },
    );

    return \%hash;
}

1;
[download]

my_script.pl :

use strict; use warnings;
use MyLib;

my $hashref = MyLib::get_data();
my %hash = %{ $hashref };
for my $key ( keys %hash ) {
    printf( 'Value of `a` in %s is %s', $key, $hash{ $key }->{'a'} );
}

__END__
[download]

Or, use a data format suited to hashes:

my_data.yaml :

---
A:
    a: 1
    b: 2
B:
    a: 3
    b: 4
[download]

my_script2.pl :

use strict; use warnings;
use YAML qw/ LoadFile /;

my $hashref = LoadFile('my_data.yaml');
my %hash = %{ $hashref };
for my $key ( keys %hash ) {
    printf( "Value of `a` in %s is %s', $key, $hash{ $key }->{'a'} );
}

__END__
[download]

Hope this helps!

The way forward always starts with a minimal test.

Comment on Re: Accessing the hash name in perl Select or Download Code

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Re^2: Accessing the hash name in perl by Sonali (Novice) on Mar 23, 2017 at 10:40 UTC
The hash structure is generated, so I can't change the structure of it, just extract it and modify it	[reply]
Re^3: Accessing the hash name in perl by huck (Prior) on Mar 23, 2017 at 13:13 UTC
The hash structure is generated, so I can't change the structure of it, just extract it Sometimes you just need to take out the chainsaw. This assumes your file is just as you put it, parts always in quotes called hash1, hash2, hash3, there always are keys in quotes called paramA and paramB, and the values of those keys are always in quotes. #!/usr/local/bin/perl use strict; use warnings; Generate(); sub Generate { Process_File('hash.pm'); } sub Process_File { my $filename = shift; open(my $fh, '<:encoding(UTF-8)', $filename) or die "Could not open file '$filename' $!"; my $file=''; while (my $line=<$fh>) { $file.=$line; } for my $n (1..3) { if ($file =~ m/\'hash$n\'.+?\{(.?)\}/ms) { my $part=$1; my ($typ_s) = $part=~/\'paramA\'.?\=\>.?\'(.?)\'/ms; my ($paramb)= $part=~/\'paramB\'.?\=\>.?\'(.*?)\'/ms; print "n $n typ_s $typ_s paramb $paramb\n"; } # part } # n } [download] Result `D:\goodies\pdhuck\down1\perl\monks>perl 1185438.pl n 1 typ_s 00 paramb FF n 2 typ_s 01 paramb 02 n 3 typ_s 00 paramb 03` [download] Im sure others can improve on this too.	[reply] [d/l] [select]