Lesson plan
Actor (programming language)
The Actor programming language was invented by Charles Duff of The Whitewater Group in 1988. It was an offshoot of some object-oriented extensions to the Forth language he had been working on. Actor is a pure object-oriented language in the style of Smalltalk. Like Smalltalk, everything is an object, including small integers. A Baker semi-space garbage collector is used, along with (in memory-constrained Windows 2.1 days) a software virtual memory system that swaps objects. A token threaded interpreter, written in 16-bit x86 assembly language, executes compiled code. Actor only was released for Microsoft Windows 2.1 and 3.0. Actor used a pure object-oriented framework over native operating system calls as its basic GUI architecture. This allows an Actor application to look and feel exactly like a Windows application written in C, but with all the advantages of an interactive Smalltalk-like development environment. Both a downside and upside to this architecture is a tight coupling to the Windows architecture, with a thin abstraction layer into objects. This allows direct use of the rich Windows OS API, but also makes it nearly impossible to support any other OS without a significant rewrite of the application framework. A demo of Actor was shown in an episode of Computer Chronicles.
Article summary
The Actor programming language was invented by Charles Duff of The Whitewater Group in 1988. It was an offshoot of some object-oriented extensions to the Forth language he had been working on. Actor is a pure object-oriented language in the style of Smalltalk. Like Smalltalk, everything is an object, including small integers. A Baker semi-space garbage collector is used, along with (in memory-constrained Windows 2.1 days) a software virtual memory system that swaps objects. A token threaded interpreter, written in 16-bit x86 assembly language, executes compiled code. Actor only was released for Microsoft Windows 2.1 and 3.0. Actor used a pure object-oriented framework over native operating system calls as its basic GUI architecture. This allows an Actor application to look and feel exactly like a Windows application written in C, but with all the advantages of an interactive Smalltalk-like development environment. Both a downside and upside to this architecture is a tight coupling to the Windows architecture, with a thin abstraction layer into objects. This allows direct use of the rich Windows OS API, but also makes it nearly impossible to support any other OS without a significant rewrite of the application framework. A demo of Actor was shown in an episode of Computer Chronicles.
Key claims
No claims recorded.
Discussion questions
- Summarise the article in your own words. Which single claim would you verify first, and why?
- Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
- If two sources disagreed about one of these facts, what would you need in order to trust one over the other?
Bibliography
No sources recorded.
Key claims and bibliography are generated from the same tracked claims and sources as the article page.