![]() |
Introductory Notes: Sather Programming Language |
The programming language Sather was originally designed and developed at the International Computer Science Institute (ICSI) affiliated with the department of computer science of the University of California at Berkeley.
The language takes its' name from the Sather tower - the best-known landmark on the Berkeley campus. The tower was designed as a copy of St Mark's Campanile in Venice, Italy.
Sather was originally envisaged as an efficient, cleaned up, alternative to the language Eiffel. Since its conception, however, the two languages have evolved to be quite distinct. Sather's principal features are :-
A formal language specification is in the course of being written.
The formal definition of the Sather language includes only three pervasive implementation classes - BIT, BOOL and REFERENCE. There is also a small number of pervasive abstract classes and "constructor" classes which provide the basis on which all other classes may be defined. In order to provide a useful implementation it has been decided that an implementation which conforms to the specification must also include classes specified in a Required Library (everything from bit-patterns to text, from date/time to file systems, etc).
It is expected that implementers or, indeed, library users too will offer additional libraries as they deem fit. It is expected that these will include such general topics as Windowing, Networks, Mathematics and specialist extensions of the Required Library. Some notes on libraries in general will be found in the library documentation of the Sather W implementation of the language.
The formal specification of the Sather language includes a reference to the need for an implementation to provide facilities for internationalising programs and providing localisation facilities. The model specified includes the implementation of the two standards -
ISO/IEC 14651 - International String Ordering - Method for comparing Character Strings and Description of the Common Template Tailorable Ordering
ISO/IEC 14652 - Information Technology - Specifications for Cultural Conventions
These standards are available from national standards bodies, a list of whose members may be obtained from ISO.
The need to be able to run a program without alteration in whatever cultural environment it may be has meant that the Required Library include a number of classes specifically for use where a variety of cultures may be in use. Any full implementation of the internationalised Sather language must therefore include facilities for converting a cultural specification (as given in the appropriate standards and as may be registered with national standards bodies) into a form suitable for use when running Sather programs.
Since "message" files may be needed not only in a variety of languages, but also in a range of encodings, it is as a minimum necessary to have the ability to convert from one encoding to another. This requires an implementation to provide such a re-encoding utility.
Comments
or enquiries should be made to Keith
Hopper . Page last modified: Tuesday, 16 May 2000. |
![]() |