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

Comment on Extracting values from hash Download Code

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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]


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