Extracting values from hash

Sun751 has asked for the wisdom of the Perl Monks concerning the following question:

To get rid of too many variables I used hash to record all my records in it,

sub initilize_config
{
    my ($HR_config,$file) = @_;
    open (my $fr, '<', "$file") || die "Unable to open configuration f
+ile: $file $!";
    while (my $line = <$fr>)
    {
        $line =~ tr/\r\n//d;
        next unless $line;
        if ($line =~ /=/)
        {
            my ($key,$val)=$line=~ /^(.*?)=(.*?)$/;
            $$HR_config{$key} = $val;
        }
    }
}
[download]

the key of the hash is constant where as value always change so in some subroutine if I want to extract and use the value of some key, suppose "xyz". How can that be done? Can any one suggest me please!!! Cheers

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Re: Extracting values from hash by moritz (Cardinal) on Jul 01, 2009 at 08:25 UTC
See perldata and perlreftut, you can access the value of a hash reference like this: `$HR_config->{xyz}`.	[reply] [d/l]
Re: Extracting values from hash by jrsimmon (Hermit) on Jul 01, 2009 at 11:39 UTC
Here's a short little script that you can play with to see how this works. use strict; use warnings; my %HR_config= (); my $cfgFile = "c:\\temp\\cfg.ini"; &initiliaze_config(\%HR_config, $cfgFile); my (@retVals) = &retrieve_config(\%HR_config); print "Values from the returned array:\t@retVals\n"; my @keys = keys(%HR_config); print "Keys from the populated hash:\t@keys\n"; my @hashVals = map ($HR_config{$_}, @keys); print "Values from the populated hash:\t@hashVals\n"; sub initiliaze_config { my ($HR_config,$file) = @_; open (my $fr, '<', "$file") \|\| die "Unable to open configuration f +ile: $file $!"; while (my $line = <$fr>) { $line =~ tr/\r\n//d; next unless $line; if ($line =~ /=/) { my ($key,$val)=$line=~ /^(.?)=(.?)$/; $$HR_config{$key} = $val; } } } sub retrieve_config { my $HR_config = pop(@_); my @values = (); foreach my $key (keys(%{$HR_config})){ my $value = $HR_config->{$key}; push(@values, $value); } return (@values); } [download]	[reply] [d/l]