Module simple_locale::settings

Parent to a set of operating system, locale functions.

Typically we treat each of the categories defined by POSIX in locale.h as modules. The categories are show in the table below.

POSIX Category	Module	Function(s)
LC_COLLATE	N/A
LC_CTYPE	codeset	get_code_set_format, get_code_set_format_for_locale
LC_MESSAGES	messages	get_message_format, get_message_format_for_locale
LC_MONETARY	currency	get_currency_format, get_currency_format_for_locale
LC_NUMERIC	numeric	get_numeric_format, get_numeric_format_for_locale
LC_TIME	time	get_date_time_format, get_date_time_format_for_locale, get_calendar_names, get_calendar_names_for_locale

Note: the POSIX category LC_COLLATE is not mapped to modules as there are no calls to retrieve specific information.

For each module there is at least a matching pair of functions, one which takes zero parameters and returns the current locale settings, and one which takes two parameters and allows the retrieval of settings from another locale. The first of these parameters is a Locale enum that denotes the locale to query, and the second parameter is a boolean inherit_current that determines how the specified locale should be interpreted.

Additionally, the module locale has the necessary functions to get and set the locale either for an individual category or for all. This modules provides implementations that use the C API directly as well as an implementation that uses standard environment variables.

Relationship to the POSIX API

The POSIX locale API is spread across a number of functions including localeconv, nl_langinfo, and setlocale. Also, the different categories of data is mixed up in common structures. The intent of this crate is to invert this abstraction, to group together data by common category regardless of the underlying API being used.

Those functions in the table above that end in _for_locale use the xlocale extended API, specifically newlocale, uselocale, and freelocale to obtain the settings for a locale other than the current.

Modules

codeset	Fetch locale-specific code-set settings.
currency	Fetch locale-specific currency formatting settings.
locale	Provides ability to get/set the current process locale.
messages	Fetch locale-specific message formatting settings.
numeric	Fetch locale-specific number formatting settings.
time	Fetch locale-specific date and time formatting settings.