Ordered hashes for Perl

 This module implements an ordered hash, meaning that it associates keys
 with values like a Perl hash, but keeps the keys in a consistent order.
 .
 Tie::Hash::Indexed is intentionally very similar to other ordered hash
 modules, most prominently Hash::Ordered. However, Tie::Hash::Indexed is
 written completely in XS and is, often significantly, faster than other
 modules. For a lot of operations, it's more than twice as fast as
 Hash::Ordered, especially when using the object-oriented interface instead of
 the tied interface. Other modules, for example Tie::IxHash, are even slower.
 .
 The object-oriented interface of Tie::Hash::Indexed is almost identical to
 that of Hash::Ordered, so in most cases you should be able to easily replace
 one with the other.