Groups | Search | Server Info | Login | Register
Groups > comp.lang.c > #393150
| From | Keith Thompson <Keith.S.Thompson+u@gmail.com> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: Loops (was Re: do { quit; } else { }) |
| Date | 2025-05-04 13:52 -0700 |
| Organization | None to speak of |
| Message-ID | <877c2wp07z.fsf@nosuchdomain.example.com> (permalink) |
| References | (16 earlier) <vtj97r$1i3v3$1@dont-email.me> <vtl166$36p6b$1@dont-email.me> <vtlcg0$3f46a$2@dont-email.me> <20250415153419.00004cf7@yahoo.com> <86h62078i8.fsf@linuxsc.com> |
Tim Rentsch <tr.17687@z991.linuxsc.com> writes:
> Michael S <already5chosen@yahoo.com> writes:
[...]
>> I suspect that 'while' loop is here in C because Dennis Ritchie wanted
>> 'do .. while() ' and thought that if the keyword is here anyway than
>> why not reuse it?
>
> According to K&R, all of the basic control structures in C -- if,
> while, for, do, and switch (and listed in that order) -- were
> provided in BCPL, though not using the same syntax as in C,.
K&R1 does say that. K&R2 dropped that statement.
BCPL's equivalent of C's do/while did not reuse the WHILE keyword.
From K&R1 :
C provides the fundamental flow-control constructions required
for well-structured programs: statement grouping; decision
making (if); looping with the termination test at the top
(while, for), or at the bottom (do); and selecting one of a
set of possible cases (switch). (All of these were provided
in BCPL as well, though with somewhat different syntax; that
language anticipated the vogue for "structured programming"
by several years.)
Today being Star Wars Day, I'll say that this is true "from a certain
point of view". The statement in K&R1 is accurate, but it could be
misinterpreted to imply that BCPL had an equivalent to the C-style
for loop. The BCPL for-command had two forms:
FOR N = expression1 TO expression2 BY constant-expression
DO command
and
FOR N = expression1 TO expression2 DO command
BCPL also had:
WHILE expression DO command
command REPEATWHILE expression // like C's do/while
UNTIL expression DO command
command REPEATUNTIL expression
command REPEAT // an infinite loop
Of course you could write the equivalent of a C-style for loop
using other constructs.
--
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
void Void(void) { Void(); } /* The recursive call of the void */
Back to comp.lang.c | Previous | Next — Previous in thread | Find similar
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-04 07:31 -0700
Re: Loops (was Re: do { quit; } else { }) Michael S <already5chosen@yahoo.com> - 2025-05-04 18:08 +0300
Re: Loops (was Re: do { quit; } else { }) Michael S <already5chosen@yahoo.com> - 2025-05-05 10:42 +0300
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-10 06:43 -0700
Re: Loops (was Re: do { quit; } else { }) Muttley@dastardlyhq.com - 2025-05-10 15:56 +0000
Re: Loops (was Re: do { quit; } else { }) scott@slp53.sl.home (Scott Lurndal) - 2025-05-10 17:48 +0000
Re: Loops (was Re: do { quit; } else { }) Muttley@dastardlyhq.com - 2025-05-11 08:20 +0000
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-10 14:29 -0700
Re: Loops (was Re: do { quit; } else { }) Muttley@dastardlyhq.com - 2025-05-11 08:21 +0000
Re: Loops (was Re: do { quit; } else { }) David Brown <david.brown@hesbynett.no> - 2025-05-11 12:02 +0200
Re: Loops (was Re: do { quit; } else { }) Muttley@dastardlyhq.com - 2025-05-11 15:30 +0000
Re: Loops (was Re: do { quit; } else { }) scott@slp53.sl.home (Scott Lurndal) - 2025-05-11 16:29 +0000
Re: Loops (was Re: do { quit; } else { }) David Brown <david.brown@hesbynett.no> - 2025-05-11 18:49 +0200
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-11 14:41 -0700
Re: Loops (was Re: do { quit; } else { }) James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-05-11 17:43 -0400
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-11 15:06 -0700
Re: Loops (was Re: do { quit; } else { }) James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-05-11 18:30 -0400
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-11 18:15 -0700
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-11 19:09 -0700
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-12 00:16 -0700
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-12 02:23 -0700
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-12 07:19 -0700
Re: Loops (was Re: do { quit; } else { }) Richard Heathfield <rjh@cpax.org.uk> - 2025-05-12 15:34 +0100
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-12 22:42 -0700
Re: Loops (was Re: do { quit; } else { }) Richard Heathfield <rjh@cpax.org.uk> - 2025-05-13 07:31 +0100
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-14 21:12 -0700
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-13 09:30 -0700
Re: Loops (was Re: do { quit; } else { }) Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-05-13 22:28 +0200
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-12 13:31 -0700
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-14 20:44 -0700
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-14 21:45 -0700
Re: Loops (was Re: do { quit; } else { }) David Brown <david.brown@hesbynett.no> - 2025-05-12 17:24 +0200
Re: Loops (was Re: do { quit; } else { }) James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-05-12 00:07 -0400
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-12 00:43 -0700
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-12 02:27 -0700
Re: Loops (was Re: do { quit; } else { }) David Brown <david.brown@hesbynett.no> - 2025-05-12 17:18 +0200
Re: Loops (was Re: do { quit; } else { }) James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-05-12 19:53 -0400
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-12 23:03 -0700
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-12 19:04 -0700
Re: Loops (was Re: do { quit; } else { }) David Brown <david.brown@hesbynett.no> - 2025-05-12 17:08 +0200
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-12 13:38 -0700
Re: Loops (was Re: do { quit; } else { }) David Brown <david.brown@hesbynett.no> - 2025-05-13 12:41 +0200
Re: Loops (was Re: do { quit; } else { }) Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-05-13 23:16 +0200
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-13 14:35 -0700
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-13 15:10 -0700
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-13 15:41 -0700
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-13 18:38 -0700
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-13 19:37 -0700
Re: Loops (was Re: do { quit; } else { }) James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-05-13 23:54 -0400
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-13 21:19 -0700
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-13 21:12 -0700
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-13 22:38 -0700
Re: Loops (was Re: do { quit; } else { }) Kaz Kylheku <643-408-1753@kylheku.com> - 2025-05-14 03:35 +0000
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-13 21:54 -0700
Re: Loops (was Re: do { quit; } else { }) Kaz Kylheku <643-408-1753@kylheku.com> - 2025-05-14 06:31 +0000
Re: Loops (was Re: do { quit; } else { }) David Brown <david.brown@hesbynett.no> - 2025-05-14 13:00 +0200
Re: Loops (was Re: do { quit; } else { }) Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-05-14 13:20 +0200
Re: Loops (was Re: do { quit; } else { }) James Kuyper <jameskuyper@alumni.caltech.edu> - 2025-05-14 23:20 -0400
Re: Loops (was Re: do { quit; } else { }) David Brown <david.brown@hesbynett.no> - 2025-05-15 11:23 +0200
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-11 17:59 -0700
Re: Loops (was Re: do { quit; } else { }) Muttley@DastardlyHQ.org - 2025-05-12 10:11 +0000
Re: Loops (was Re: do { quit; } else { }) Michael S <already5chosen@yahoo.com> - 2025-05-12 17:09 +0300
Re: Loops (was Re: do { quit; } else { }) Michael S <already5chosen@yahoo.com> - 2025-05-11 01:09 +0300
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-11 17:30 -0700
Re: Loops (was Re: do { quit; } else { }) Michael S <already5chosen@yahoo.com> - 2025-05-12 16:18 +0300
Re: Loops (was Re: do { quit; } else { }) Tim Rentsch <tr.17687@z991.linuxsc.com> - 2025-05-14 11:09 -0700
Re: Loops (was Re: do { quit; } else { }) Janis Papanagnou <janis_papanagnou+ng@hotmail.com> - 2025-05-13 15:57 +0200
Re: Loops (was Re: do { quit; } else { }) Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2025-05-04 13:52 -0700
csiph-web