The A-0 system (Arithmetic Language version 0), written by Grace Murray Hopper in 1951 and 1952 for the UNIVAC I, was an early compiler related tool developed for electronic computers. The A-0 functioned more as a loader or linker than the modern notion of a compiler. A program was specified as a sequence of subroutines and its arguments. The subroutines were identified by a numeric code and the arguments to the subroutines were written directly after each subroutine code. The A-0 system converted the specification into machine code that could be fed into the computer a second time to execute the said program.
The A-0 system was followed by the A-1, A-2, A-3 (released as ARITH-MATIC), AT-3 (released as MATH-MATIC) and B-0 (released as FLOW-MATIC).
The A-2 system was developed at the UNIVAC division of Remington Rand in 1953 and released to customers by the end of that year. Customers were provided the source code for A-2 and invited to send their improvements back to UNIVAC. Thus, A-2 could be considered an example of the result of an early philosophy similar to free and open-source software.
- ^ Ridgway, Richard (1952). "Compiling routines". Proceeding ACM '52 Proceedings of the 1952 ACM National Meeting (Toronto): 1–5. doi:10.1145/800259.808980. S2CID 14878552.
- ^ "List of early compilers and assemblers".
- ^ Hopper "Keynote Address", Sammet pg. 12
- ^ *"PAPERS: Automatic Programming: The A 2 Compiler System -- Part I" (PDF). Computers and Automation. 4 (9): 25–29. Sep 1955. Retrieved 2020-09-05.
- "PAPERS: Automatic Programming: The A 2 Compiler System -- Part II" (PDF). Computers and Automation. 4 (10): 15–27. Oct 1955. Retrieved 2020-09-05.
- ^ Ceruzzi, Paul (1998). A History of Modern Computing. The MIT Press.
- ^ "Heresy & Heretical Open Source: A Heretic's Perspective".
- Proceedings of the 1954 MIT Summer Session on "Digital Computers - Advanced Coding Techniques, section 7 - A2 Compiler and Associated Routines for use with Univac
- Hopper, Grace (May 1952). "The Education of a Computer" (PDF). Proceedings of the Association for Computing Machinery Conference (Pittsburgh) May 1952. pp. 243–249. doi:10.1145/609784.609818.
- Hopper, Grace (16 February 1955). "Automatic Coding for Digital Computers" (PDF). High Speed Computer Conference (Louisiana State University) February 1955. Remington Rand.
- Hopper, Grace. "Keynote Address". Proceedings of the ACM SIGPLAN History of Programming Languages (HOPL) conference.
- Ridgway, Richard K. (1952). "Compiling Routines". Proceedings of the 1952 ACM national meeting (Toronto) ACM '52.
- Sammet, Jean (1969). Programming Languages: History and Fundamentals. Prentice-Hall. pp. g. 12.