This sounds like a job for a hash of hashes! Using the code below, you can get at the keys by referring to keys %hash and you can get at all of the values of key2, for example, by referring to keys %{$hash{key2}}
use strict;
my $data = "key1=valuea key2=valuea valueb key3=valuea valueb valuec k
+ey4=valuea key5=valuea key6=valuea valueb";
my %hash = ParseData($data);
print "All of the keys are: ", join(" ",keys %hash),"\n\n";
print "Key2's keys are: ", join(" ",keys %{$hash{key2}});
sub ParseData {
my $datastring = shift;
my %data;
my $currkey;
foreach (split(' ',$datastring)) {
if (/=/) {
my $val;
($currkey, $val) = split('=');
$data{$currkey}{$val}++;
}
else {
$data{$currkey}{$_}++;
}
}
return %data;
}