And, for those who have been contemplating parameter widening: on the 68000, insert s += 3. For "portable" C89 code, declare the parameter an int (not char) -- then introduce char c2 = c and s = &c2 instead. This transformation is "safe" because parameters are copied by value and cannot be returned that way.
As to debugging -- many of these systems did not have "debuggers" -- an example would be Whitesmiths C in the late 70s and the 80s. We used a strategy of old-school paper validation, combined with function testing. Yes, things moved more slowly.
Code can be maintained. The above C89 code was just compiled with gcc 9.2.1 -- with gcc -std=c89 c89.c it compiled without warning, and ran (40 year old code).
The issue with (say) bring forward Whitesmiths C is that the Whitesmiths standard library is not POSIX. Not hard to convert, though. For example (as I recall) %d was %i
FORTRAN 77 (and FORTRAN IV) is in a similar category. As is COBOL and Common LISP.
SNOBOL4 is a bit of an outlier -- The original interpreter was written in macro assembler. That assembler is now converted to C, and the original interpreter can still be run:
The Macro Implementation of SNOBOL4 in C (CSNOBOL4BX) Version 2.0
by Philip L. Budne, January 1, 2015
SNOBOL4 (Version 3.11, May 19, 1975)
BLOCKS (Version 1.10, April 1, 1973)
Bell Telephone Laboratories, Incorporated
EXTENSIONS (Version 0.25, June 16, 2015)
Fred Weigel
No errors detected in source program
CODE (TUE AUG 4 10:28:58 EDT 2015)
RUNNING ON CSNOBOL4 MAINBOL WITH SPITBOL, BLOCKS, EXTENSIONS
ENTER SNOBOL4 STATEMENTS (TRY ? FOR HELP)
5,541,616 BYTES FREE
CODE:
And, yes, I modified the original interpreter to add some extensions back in 2015. However, Budne has published the pattern matching engine in Javascript so there is an easy migration for those programs (https://github.com/philbudne/spipatjs).
In my opinion (and this is strictly my opinion), only Javascript appears to have this "lasting" property wrt modern languages. An important characteristic is simplicity, and forward-backward compatibility. As well, multiple implementations are important.
As to debugging -- many of these systems did not have "debuggers" -- an example would be Whitesmiths C in the late 70s and the 80s. We used a strategy of old-school paper validation, combined with function testing. Yes, things moved more slowly.
Code can be maintained. The above C89 code was just compiled with gcc 9.2.1 -- with gcc -std=c89 c89.c it compiled without warning, and ran (40 year old code).
The issue with (say) bring forward Whitesmiths C is that the Whitesmiths standard library is not POSIX. Not hard to convert, though. For example (as I recall) %d was %i
FORTRAN 77 (and FORTRAN IV) is in a similar category. As is COBOL and Common LISP.
SNOBOL4 is a bit of an outlier -- The original interpreter was written in macro assembler. That assembler is now converted to C, and the original interpreter can still be run:
The Macro Implementation of SNOBOL4 in C (CSNOBOL4BX) Version 2.0 by Philip L. Budne, January 1, 2015 SNOBOL4 (Version 3.11, May 19, 1975) BLOCKS (Version 1.10, April 1, 1973) Bell Telephone Laboratories, Incorporated EXTENSIONS (Version 0.25, June 16, 2015) Fred Weigel
No errors detected in source program
CODE (TUE AUG 4 10:28:58 EDT 2015) RUNNING ON CSNOBOL4 MAINBOL WITH SPITBOL, BLOCKS, EXTENSIONS ENTER SNOBOL4 STATEMENTS (TRY ? FOR HELP) 5,541,616 BYTES FREE CODE:
And, yes, I modified the original interpreter to add some extensions back in 2015. However, Budne has published the pattern matching engine in Javascript so there is an easy migration for those programs (https://github.com/philbudne/spipatjs).
In my opinion (and this is strictly my opinion), only Javascript appears to have this "lasting" property wrt modern languages. An important characteristic is simplicity, and forward-backward compatibility. As well, multiple implementations are important.
FredW