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Sather is an object-oriented programming language. It originated circa 1990 at the International Computer Science Institute (ICSI) at the University of California, Berkeley, developed by an international team led by Steve Omohundro. It supports garbage collection and generics by subtypes. Originally, it was based on Eiffel, but it has diverged, and now includes several functional programming features. It is probably best to view it as an object-oriented language, with many ideas borrowed from Eiffel. Even the name is inspired by Eiffel; the Sather Tower is a recognizable landmark at Berkeley, named after Jane Krom Sather, the widow of Peder Sather, who donated large sums to the foundation of the university. Sather also takes inspiration from other programming languages and paradigms: iterators, design by contract, abstract classes, multiple inheritance, anonymous functions, operator overloading, contravariant type system. The original Berkeley implementation (last stable version 1.1 was released in 1995, no longer maintained〔(ICSI Sather future plans )〕) has been adopted by the Free Software Foundation therefore becoming GNU Sather. Last stable GNU version (1.2.3) was released in July 2007〔(GNU Sather downloads )〕 and the software is currently not maintained. There were several other variants: Sather-K from the University of Karlsruhe;〔(Sather-K project page ) (archive from year 2001)〕〔(Sather-K 0.9 download, version from year 1994 )〕 Sather-W from the University of Waikato〔(Sather-W 1.3 project page ) (archived link from year 2002)〕 (implementation of Sather version 1.3); Peter Naulls' port of ICSI Sather 1.1 to RISC OS;〔Peter Naulls' port is no longer available on the Web.〕 and pSather,〔(pSather description )〕〔(pSather download )〕 a parallel version of ICSI Sather addressing non-uniform memory access multiprocessor architectures but presenting a shared memory model to the programmer. The former ICSI Sather compiler (now GNU Sather) is implemented as a compiler to C, i.e., the compiler does not output object or machine code, but takes Sather source code and generates C source code as an intermediate language. Optimizing is left to the C compiler. The GNU Sather compiler, written in Sather itself, is dual licensed under the GNU GPL & LGPL. == Hello World == class HELLO_WORLD is main is #OUT+"Hello World\n"; end; end; A few remarks: * Class names are ALL CAPS; this is not only a convention but is enforced by the compiler. * The method called main is the entry point for execution. It may belong to any class, but if this is different from MAIN, it must be specified as a compiler option.* # is the constructor symbol, calling method create of the corresponding class; here it is used for instantiating the OUT class, which is actually stdout.* The + operator has been overloaded here to stand for stream append.* Operators such as + are syntactic sugar for conventionally named method calls: a + b stands for a.plus(b). The usual arithmetic precedence conventions are used to resolve the calling order of methods in complex formulae.* The program layout allows for pre- and post-conditions (not shown here), showing Sather's Eiffel lineage. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Sather」の詳細全文を読む スポンサード リンク
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