Modula-2+ is a programming language descended from the Modula-2 language. It was developed at DEC Systems Research Center (SRC) and Acorn Computers Ltd Research Centre in Palo Alto, California. Modula-2+ is Modula-2 with exceptions and threads. The group which developed the language was led by P. Rovner in 1984.
Main differences with Modula-2:
- Concurrency; different than the concept of coroutine, which was already part of Modula-2
- Exception handling
- Garbage collection
Implementations
Modula-2+ was used to develop Topaz, an operating system for the SRC DEC Firefly shared memory asymmetric multiprocessing workstation.4 Most Topaz applications were written in Modula-2+, which grew along with the development of the system.5 Modula-2+ was also used by Acorn in the ARX operating system, and to build an integrated development environment in the Acorn Research Center (ARC).6 Modula-2+ strongly influenced other languages such as Modula-3, but as of 2005, it had disappeared.
The original developers of Modula-2+ were both acquired: Acorn by Olivetti and Digital Equipment Corporation by Compaq. Compaq was bought by Hewlett-Packard. Olivetti sold the Olivetti Research Center and Olivetti Software Technology Laboratory (after bought Acorn ARC) to Oracle Corporation and was later absorbed by AT&T.7 DEC have made the SRC-reports available to the public.
See also
References
Rovner, Paul; Levin, Roy; Wick, John (January 11, 1985). SRC-RR-3 On extending Modula-2 for building large, integrated systems. Hewlett-Packard Labs (Report). http://www.hpl.hp.com/techreports/Compaq-DEC/SRC-RR-3.html ↩
DeTreville, John (November 22, 1990). Experience with concurrent garbage collectors for Modula-2+ SRC-RR-64. Hewlett-Packard Labs (Report). http://www.hpl.hp.com/techreports/Compaq-DEC/SRC-RR-64.html ↩
DeTreville, John (November 22, 1990). Experience with concurrent garbage collectors for Modula-2+ SRC-RR-64. Hewlett-Packard Labs (Report). http://www.hpl.hp.com/techreports/Compaq-DEC/SRC-RR-64.html ↩
Thacker, Charles P.; Stewart, Lawrence C.; Satterthwaite, Edwin H. Jr. (December 30, 1987). Firefly: a multiprocessor workstation SRC-RR-23. Hewlett-Packard Labs (Report). /wiki/Charles_P._Thacker ↩
McJones, Paul R.; Swart, Garret F. (September 28, 1987). Evolving the Unix system interface to support multithreaded programs SRC-RR-21. Hewlett-Packard Labs (Report). http://www.hpl.hp.com/techreports/Compaq-DEC/SRC-RR-21.html ↩
Cardelli, Luca; Donahue, James; Glassman, Lucille; Jordan, Mick; Kalsow, Bill; Nelson, Greg (November 1989). Modula-3 Report (revised), Research Report 52, SRC-RR-052. Hewlett-Packard Labs (Report). DEC Systems Research Center (SRC). ftp://apotheca.hpl.hp.com/pub/dec/SRC/research-reports/abstracts/src-rr-052.html ↩
Kossow, Al (August 2001). "Not a RISC by Thursday". Newsgroup alt.folklore.computers,comp.sys.acorn.misc. http://neil.franklin.ch/Usenet/alt.folklore.computers/20010824_Not_A_RISC_By_Thursday ↩