Support for extended locales

It is sometimes desirable for applications to use message catalog files to store information other than localized messages. To avoid confusing the language, territory, and character set triples used to store this additional information with those that contain localized messages the notion of extended locale has been adopted. An extended locale is defined as a language, territory, character set triple where the language string begins with the '$' character.

Extended locales are intended to be used to identify objects other than localized messages which are stored in message catalog files. For example, the #('$Comment' 'Comment' 'Comment') extended locale could be used by an application to maintain a comment about the message catalog file.

The following protocols are provided to determine what language, territory, and character set combinations are supported by a message catalog file. Each of the following protocols answers a collection of ordered triples representing the language, territory, and character sets for which application-defined objects or localized messages have been stored. The following protocols report errors by answering nil.

messageIdentifiers

Answers a collection containing language, territory, and character set triples from which localized messages are stored, excluding objects stored for extended locales.

hiddenMessageIdentifiers

Answers a collection containing language, territory, and character set triples which are used to identify extended locales.

allMessageIdentifiers

Answers a collection containing all language, territory, and character set triples for which messages are stored, including objects stored for extended locales.

The following example illustrates the use of the preceding protocols:

"A code fragment to determine the locales and character sets

supported by a message catalog file."

| catalog translations extendedLocales allIdentifiers |

catalog := NlsMessageCatalog on: 'demo.cat'.

translations := catalog messageIdentifiers.

extendedLocales := catalog hiddenMessageIdentifiers.

allIdentifiers := catalog allMessageIdentifiers

^Array

with: translations

with: extendedLocales

with: allIdentifiers

As a convenience, the NlsMessageCatalog provides the supportsLanguage:territory:characterSet: message to determine if a message catalog file supports a particular language, territory, and character set combination. This message answers a Boolean value indicating whether or not the requested combination is supported. The following example demonstrates how to use the supportsLanguage:territory:characterSet: protocol.

"Testing a message catalog file to determine if messages are stored

for #('english' 'us' 'iso8859-1')."

| catalog |

catalog := NlsMessageCatalog on: 'demo.cat'.

^catalog

supportsLanguage: 'english'

territory: 'us'

characterSet: 'iso8859-1'

 

Note:

The messageIdentifiers message is useful for selecting an alternative set of localized messages if the supportsLanguage:territory:characterSet: message indicates that no messages are available for the requested language, territory, and character set.