Hash::Flatten

If you are in need of a Perl module that can easily and effectively convert a nested hash structure to a flat hash of delimited key-value pairs and vice versa, then Hash::Flatten is the software for you. It serves as a very useful tool for protocols that only support key-value pairs, such as CGI and DBMs.

This software provides a functional interface with the command $flat_hash = flatten($nested_hash, \%options), which helps to reduce a nested data-structure to key-value form. However, it should be noted that the top-level container must be a hashref. A sample code for this would be:

$nested = {
'x' => 1,
'y' => {
'a' => 2,
'b' => 3
},
'z' => [
'a', 'b', 'c'
]
};
$flat = flatten($nested);
use Data::Dumper;
print Dumper($flat);

This will give the following output:

$VAR1 = {
'y.a' => 2,
'x' => 1,
'y.b' => 3,
'z:0' => 'a',
'z:1' => 'b',
'z:2' => 'c'
};

It is also possible to use the \%options hashref to override the default behavior as needed.

On the other hand, the OO interface of Hash::Flatten provides a more secure option. The command $o = new Hash::Flatten(\%options) enables users to squirrel away settings, while $flat = $o->flatten($nested) flattens the structure and $nested = $o->unflatten($flat) unflattens the structure, while using the options stored in the object.

The SYNOPSIS section provides examples of the functions used in Hash::Flatten. By using the command 'use Hash::Flatten qw(:all);' users can access the exported functions of the software easily.

Overall, Hash::Flatten provides an effective and useful tool for converting nested hash structures to flattened hashes and back again. It has both a functional and OO interface, providing a secure means of using the software.