Functions to implement the ordinal rule-based-number-format rules of CLDR.

As CLDR notes, the data is incomplete or non-existent for many languages. It is considered complete for English however.

The standard public API for RBNF is via the Cldr.Number.to_string/2 function.

The functions on this module are defined at compile time based upon the RBNF rules defined in the Unicode CLDR data repository. Available rules are identified by:

iex> Cldr.Rbnf.Ordinal.rule_sets "en"
[:digits_ordinal]

A rule can then be invoked on an available rule_set. For example

iex> Cldr.Rbnf.Ordinal.digits_ordinal 123, "en"
"123rd"

This call is equivalent to the call through the public API of:

iex> Cldr.Number.to_string 123, format: :ordinal
"123rd"