ABC was the most direct predecessor of Python; I worked on it from about 1983-1986.
I downloaded these sources from cwi.nl, specifically the abc-unix tarball.
Another copy of ABC sources exists in Luciano Ramalho’s GitHub. I hope that one day I will compare and integrate both trees.
Most files have the latest modification time in the tar ball as 1991; Some have 1996 or 2021.
There are build instructions in the old README file.
Current sources assume 32-bit systems where ints and pointers have the same size. I hope that eventually the source code will be upgraded to work also on 64-bit systems (where int is 32 bit and pointers are 64 bit).
CWI never placed a license on ABC, but it says:
Copyright (c) Stichting Mathematische Centrum, Amsterdam, 1988-2011.
I’ll try to talk with Steven Pemberton eventually (hopefully MIT).
Eddie Boev, Frank van Dijk, Leo Gerts, Timo Krijnen, Lambert Mertens, Steven Pemberton, Guido van Rossum.
- Leo Geerts, Lambert Mertens and Steven Pemberton, The ABC Programmer’s Handbook, Prentice-Hall, Englewood Cliffs, New Jersey, 1990, ISBN 0-13-000027-2.
- Steven Pemberton, An Alternative Simple Language and Environment for the PC, IEEE Software, Vol. 4, No. 1, January 1987, p. 56-64. http://www.cwi.nl/~steven/abc.html
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