Re^2: Disk based hash (as opposed to RAM based)

[thomas895]

One way around the limitation would be to store your array values as joined strings:

That works for simple strings, but once you get to more diverse strings, you should probably consider a serializer. I find that JSON::XS works great for this purpose, as does Data::Dumper with an eval. The latter method may not always be the best choice, though. JSON is more portable and can be read by another non-Perl application more easily.
For example:

# Using JSON::XS
use strict;
use warnings;
use DB_File;
use JSON::XS qw( encode_json );

my %hash;

unlink "tempfile";    #Remove previous file, if any
tie %hash, "DB_File", "tempfile", O_RDWR | O_CREAT, 0666, $DB_HASH
  or die "Cannot open file 'tempfile': $!\n";

while ( $sourceString =~ /example(key)regex(value)example\b/ig ) {
    my $key   = $1;
    my $value = $2;
    my $string_to_insert = encode_json( [ $key, $value ] );
    push( @{ $hash{$key} }, $string_to_insert );    #Push the value in
+to the hash
}

#And then use decode_json() from JSON::XS somewhere else to get an arr
+ay of your values.

HTH