9 Jan
2017
9 Jan
'17
2:37 a.m.
There was thread 'Unix stories' were Stephen Bourne played role.
Here another story about Stephen Bourne. He worked first on Algol 68,
than joined the Unix team at Bell labs and wrote sh and adb. It's well
known that the if-fi and case-esac notation from Algol came to shell
syntax this way.
Maybe less know is that Bourne tried as hard as he could to make the
C code of sh and adb look like Algol, with the help of preprocessor
macros. I stumbled across this when I looked into the 2.11BSD code
base some time ago. Look at
http://www.retro11.de/ouxr/211bsd/usr/src/bin/sh/main.c.html
http://www.retro11.de/ouxr/211bsd/usr/src/bin/adb/main.c.html
to enjoy C with an Algol-look. The definitions are in
http://www.retro11.de/ouxr/211bsd/usr/src/bin/sh/mac.h.html
http://www.retro11.de/ouxr/211bsd/usr/src/bin/adb/defs.h.html
Cheers, Walter
3:54 a.m.
Thanks Walter!
I already read about Algol like C in the Bourne area and now know what
it means. I also read elsewhere that it was a act of freedom when the
Bell Lab boys freed finally themselves from the Bourne 'Algol'
influence.
On Sun, Jan 8, 2017, at 12:37 PM, Walter F.J. Mueller wrote:
There was thread 'Unix stories' were Stephen
Bourne played role.
Here another story about Stephen Bourne. He worked first on Algol 68,
than joined the Unix team at Bell labs and wrote sh and adb. It's well
known that the if-fi and case-esac notation from Algol came to shell
syntax this way.
Maybe less know is that Bourne tried as hard as he could to make the
C code of sh and adb look like Algol, with the help of preprocessor
macros. I stumbled across this when I looked into the 2.11BSD code
base some time ago. Look at
http://www.retro11.de/ouxr/211bsd/usr/src/bin/sh/main.c.html
http://www.retro11.de/ouxr/211bsd/usr/src/bin/adb/main.c.html
to enjoy C with an Algol-look. The definitions are in
http://www.retro11.de/ouxr/211bsd/usr/src/bin/sh/mac.h.html
http://www.retro11.de/ouxr/211bsd/usr/src/bin/adb/defs.h.html
Cheers, Walter
--
Kay Parker
kayparker(a)mailite.com
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http://www.fastmail.com - Send your email first class
5:14 a.m.
"Walter F.J. Mueller" <w.f.j.mueller(a)retro11.de> writes:
[...] to enjoy C with an Algol-look.
For those who enjoy Bournegol, can I also recommend the source code to
David Turner's KRC, which was ported from (EMAS) BCPL to C using a
similar approach. A sample from main.c:
STATIC VOID
DISPLAYCOM()
{ TEST HAVEID()
THEN TEST HAVE(EOL)
THEN DISPLAY(THE_ID,TRUE,FALSE); OR
TEST HAVE((TOKEN)DOTDOT_SY)
THEN { ATOM A = THE_ID; LIST X=NIL;
ATOM B = HAVE(EOL) ? (ATOM)EOL :> // BUG?
HAVEID() && HAVE(EOL) ? THE_ID :
0;
TEST B==0 THEN SYNTAX();
OR X=EXTRACT(A,B);
UNTIL X==NIL
DO { DISPLAY((ATOM)HD(X),FALSE,FALSE);
X=TL(X); } } //could insert extra line here between groups
OR SYNTAX();
OR SYNTAX();
}
http://krc-lang.org/
--
Adam Sampson <ats(a)offog.org> <http://offog.org/>
2904
days inactive
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4 comments
5 participants
participants (5)
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Adam Sampson -
Dave Horsfall -
Kay Parker -
Larry McVoy -
Walter F.J. Mueller