Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > comp.lang.c > #126766
| Subject | Re: Text Files |
|---|---|
| Newsgroups | comp.lang.c |
| References | (4 earlier) <p64768$gpj$1@dont-email.me> <TBihC.260036$w26.87474@fx47.am4> <p64qnr$b5q$1@dont-email.me> <zRmhC.24616$Dt.19656@fx18.am4> <87sha17v8y.fsf@bsb.me.uk> |
| From | bartc <bc@freeuk.com> |
| Message-ID | <nPohC.79552$f9.78674@fx02.am4> (permalink) |
| Organization | virginmedia.com |
| Date | 2018-02-15 23:36 +0000 |
On 15/02/2018 22:17, Ben Bacarisse wrote:
> bartc <bc@freeuk.com> writes:
>> You say that is simpler and clearer than writing:
>>
>> readln a, b, c
>>
>> OK.
>
> This is not a fair exchange of views. All languages have winners and
> losers in the trade-off between providing general mechanisms and
> specific ones, but no one but you has access to the documentation for
> your language so it's impossible to tell what, if anything, the cost is
> of having that simple input line.
There is no cost because you can do it the hard way too (I'm sure I can
do it how Python does it). But the benefit is easier coding and extra
productivity.
> For example, one apparent cost is that one can't distinguish between
> integer and floating point input because you've posted essentially the
> same line for both cases.
I used to support this statement for my compiled language. Then the type
would be depend on the type of the variable. In the dynamic one, the
type is automatic, or you can stipulate the type, or read items as
strings or names, and convert to numbers.
(I've briefly resurrected an old compiler - with static types like C -
which turns this:
int a, b, c
readln a, b, c
into this:
call _qreadln
call _qreadi4
mov [ebp-4],eax ;<a>
call _qreadi4
mov [ebp-8],eax ;<b>
call _qreadi4
mov [ebp-12],eax ;<c>
Really, there's no magic about it. Those functions just return 0 at EOL.
For anything a bit more elaborate there were ways to look ahead.)
That may be an advantage, of course, but it
> can also be a disadvantage.
>
> And then I don't know how can I specify what separators are permitted,
> or how I can tell if there was more or less data than needed. I can't
> even tell how to detect an input failure.
The OP wanted to know how to do something like:
read (a, b, c)
(from a file, but from console is similar).
And some languages do allow that. However, many don't seem to any more,
including Python, despite what David Brown says.
You like to bring up excuses why it can't possibly work. The idea is for
a quick, informal way of reading things without much error-checking,
because the input is trusted, or because an error is inconsequential.
If it wasn't workable, then I wouldn't have the feature. But it is, I
have, and I use it. What's the problem?
> It's not that I want to know the answers -- the point is that this is
> rapidly going turn into a fruitless exchange without full documentation
> for all the languages involved.
You don't need any docs except to know such simple input possible in
many languages without fuss, and is not possible in C and Python without
some fuss. In C, perhaps rather more of it.
In my (scripting) language I typically use such input for reading
configuration files or project files, often ones that have been written
by the same program.
A typical line might have a keyword, followed by known number of
parameters depending on keyword. How sophisticated does a read-line
routine need to be?
readln kwd:"n" # read lower-cased name as first
# item of next input line
case kwd
when "screensize" then
read cols, rows # read what should be two numbers
...
--
bartc
Back to comp.lang.c | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Text Files G B <gb@gb.com> - 2018-02-14 11:47 -0400
Re: Text Files Ed Prochak <edprochak@gmail.com> - 2018-02-14 08:45 -0800
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-14 08:47 -0800
Re: Text Files already5chosen@yahoo.com - 2018-02-15 01:17 -0800
Re: Text Files gordonb.ea2mq@burditt.org (Gordon Burditt) - 2018-02-14 11:10 -0600
Re: Text Files "James R. Kuyper" <jameskuyper@verizon.net> - 2018-02-14 12:28 -0500
Re: Text Files jt@toerring.de (Jens Thoms Toerring) - 2018-02-14 21:07 +0000
Re: Text Files Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-14 15:31 -0700
Re: Text Files Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-15 06:59 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 10:20 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-14 22:51 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-15 11:04 +0100
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-15 06:16 -0800
Re: Text Files "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2018-02-15 22:22 +0800
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-15 15:58 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 16:31 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-15 21:31 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 21:21 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 22:17 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 23:36 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 23:48 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 10:09 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 12:57 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 15:50 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 15:50 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 17:07 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 20:44 +0000
Re: Text Files Ian Collins <ian-news@hotmail.com> - 2018-02-17 11:22 +1300
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 17:48 +0000
Re: Text Files GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-16 17:06 +0100
Re: Text Files Ian Collins <ian-news@hotmail.com> - 2018-02-17 11:10 +1300
Re: Text Files supercat@casperkitty.com - 2018-02-16 14:48 -0800
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-16 15:14 -0800
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 23:25 +0000
Re: Text Files supercat@casperkitty.com - 2018-02-16 15:50 -0800
Re: Text Files already5chosen@yahoo.com - 2018-02-16 07:19 -0800
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 17:13 +0100
Re: Text Files Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-19 17:55 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-19 19:14 +0100
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-19 11:48 -0800
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-16 08:14 -0800
Re: Text Files Robert Wessel <robertwessel2@yahoo.com> - 2018-02-17 18:32 -0600
Re: Text Files jacobnavia <jacob@jacob.remcomp.fr> - 2018-02-15 22:57 +0100
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 22:58 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 00:19 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 02:26 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 02:57 +0000
Re: Text Files asetofsymbols@gmail.com - 2018-02-16 00:21 -0800
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 11:30 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 10:36 +0100
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 11:36 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 13:10 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 12:25 +0000
Re: Text Files Ike Naar <ike@iceland.freeshell.org> - 2018-03-06 19:33 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-03-06 20:55 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-16 04:42 -0800
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 16:58 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 20:02 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 21:43 +0100
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-17 04:01 -0800
Re: Text Files bartc <bc@freeuk.com> - 2018-02-17 13:10 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-17 05:27 -0800
Re: Text Files bartc <bc@freeuk.com> - 2018-02-17 14:20 +0000
Re: Text Files Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-16 09:04 -0700
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 14:31 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-16 06:42 -0800
Re: Text Files bartc <bc@freeuk.com> - 2018-02-16 14:58 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-16 07:23 -0800
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-16 15:24 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-16 04:13 -0800
Re: Text Files Siri Cruise <chine.bleu@yahoo.com> - 2018-02-16 04:29 -0800
Re: Text Files Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-20 16:41 +0000
Re: Text Files Siri Cruise <chine.bleu@yahoo.com> - 2018-02-20 09:39 -0800
Re: Text Files Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-20 19:16 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 12:46 +0000
Re: Text Files GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-15 14:52 +0100
Re: Text Files Anton Shepelev <anton.txt@g{oogle}mail.com> - 2018-02-15 17:07 +0300
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 14:23 +0000
Re: Text Files Anton Shepelev <anton.txt@g{oogle}mail.com> - 2018-02-15 18:52 +0300
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 14:39 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 15:43 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 20:32 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 22:06 +0000
Re: Text Files GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-15 23:12 +0100
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-15 15:12 -0800
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 23:43 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 23:54 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 23:35 +0000
Re: Text Files Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-16 17:07 -0800
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-17 02:38 +0000
Re: Text Files Ian Collins <ian-news@hotmail.com> - 2018-02-17 17:26 +1300
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-17 11:22 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-17 12:07 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-17 04:17 -0800
Re: Text Files Anton Shepelev <anton.txt@gmail.com> - 2018-02-17 16:25 +0300
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-17 07:35 -0800
Re: Text Files GOTHIER Nathan <nathan.gothier@gmail.com> - 2018-02-17 15:24 +0100
Re: Text Files Ian Collins <ian-news@hotmail.com> - 2018-02-18 11:10 +1300
Re: Text Files Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-19 12:05 -0800
Re: Text Files already5chosen@yahoo.com - 2018-02-19 15:32 -0800
Re: Text Files Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-21 10:34 -0800
Re: Text Files already5chosen@yahoo.com - 2018-02-21 15:35 -0800
Re: Text Files bartc <bc@freeuk.com> - 2018-02-22 00:11 +0000
Re: Text Files Robert Wessel <robertwessel2@yahoo.com> - 2018-02-21 18:26 -0600
Re: Text Files Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-21 21:39 -0800
Re: Text Files Robert Wessel <robertwessel2@yahoo.com> - 2018-02-23 03:08 -0600
Re: Text Files supercat@casperkitty.com - 2018-02-23 16:16 -0800
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-23 16:46 -0800
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-24 02:49 -0800
Re: Text Files asetofsymbols@gmail.com - 2018-02-24 05:16 -0800
Re: Text Files "F. Russell" <fr@random.info> - 2018-02-24 14:35 +0000
Re: Text Files Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-24 08:48 -0700
Re: Text Files supercat@casperkitty.com - 2018-02-25 15:09 -0800
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-25 15:54 -0800
Re: Text Files supercat@casperkitty.com - 2018-02-26 11:04 -0800
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-26 11:52 -0800
Re: Text Files supercat@casperkitty.com - 2018-02-26 14:12 -0800
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-26 14:40 -0800
Re: Text Files already5chosen@yahoo.com - 2018-02-22 04:58 -0800
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-22 05:33 -0800
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-22 13:59 +0000
Re: Text Files Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2018-02-22 07:24 -0800
Re: Text Files supercat@casperkitty.com - 2018-02-20 12:14 -0800
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-15 21:37 +0100
Re: Text Files bartc <bc@freeuk.com> - 2018-02-15 21:34 +0000
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-15 14:15 -0800
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-16 10:47 +0100
Re: Text Files "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2018-02-15 22:20 +0800
Re: Text Files "F. Russell" <fr@random.info> - 2018-02-15 15:24 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-15 16:05 +0000
Re: Text Files "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2018-02-16 00:22 +0800
Re: Text Files Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-15 13:35 -0700
Re: Text Files Anton Shepelev <anton.txt@gmail.com> - 2018-02-25 00:13 +0300
Re: Text Files bartc <bc@freeuk.com> - 2018-02-24 21:24 +0000
Re: Text Files Anton Shepelev <anton.txt@gmail.com> - 2018-02-25 14:55 +0300
Re: Text Files bartc <bc@freeuk.com> - 2018-02-25 13:00 +0000
Re: Text Files Real Troll <Real.Troll@Trolls.com> - 2018-02-24 17:35 -0400
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-24 21:36 +0000
Re: Text Files Real Troll <Real.Troll@Trolls.com> - 2018-02-24 17:45 -0400
Re: Text Files Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-24 22:51 +0000
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-24 23:56 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-25 00:14 +0000
Re: Text Files bartc <bc@freeuk.com> - 2018-02-25 00:22 +0000
Re: Text Files Anton Shepelev <anton.txt@gmail.com> - 2018-02-25 15:16 +0300
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-25 15:20 -0800
Re: Text Files Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-25 20:27 -0700
Re: Text Files gazelle@shell.xmission.com (Kenny McCormack) - 2018-02-26 06:19 +0000
Re: Text Files Anton Shepelev <anton.txt@g{oogle}mail.com> - 2018-02-26 15:35 +0300
Re: Text Files Reinhardt Behm <rbehm@hushmail.com> - 2018-02-26 20:53 +0800
Grammar Patrol (Was: Text Files) gazelle@shell.xmission.com (Kenny McCormack) - 2018-02-26 17:54 +0000
Re: Text Files Jorgen Grahn <grahn+nntp@snipabacken.se> - 2018-02-26 15:27 +0000
Re: Text Files Anton Shepelev <anton.txt@g{oogle}mail.com> - 2018-02-26 18:50 +0300
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-26 09:26 -0800
Re: Text Files scott@slp53.sl.home (Scott Lurndal) - 2018-02-26 19:46 +0000
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-27 09:04 +0100
Re: Text Files already5chosen@yahoo.com - 2018-02-27 00:56 -0800
Re: Text Files Ian Collins <ian-news@hotmail.com> - 2018-02-27 22:07 +1300
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-27 14:37 +0100
Re: Text Files already5chosen@yahoo.com - 2018-02-27 07:38 -0800
Re: Text Files supercat@casperkitty.com - 2018-02-27 09:18 -0800
Re: Text Files David Brown <david.brown@hesbynett.no> - 2018-02-27 10:15 +0100
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-27 08:53 -0800
Re: Text Files Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-26 23:14 -0800
Re: Text Files Joe Pfeiffer <pfeiffer@cs.nmsu.edu> - 2018-02-26 08:32 -0700
Re: Text Files Keith Thompson <kst-u@mib.org> - 2018-02-26 09:17 -0800
Re: Text Files Tim Rentsch <txr@alumni.caltech.edu> - 2018-02-26 22:55 -0800
Re: Text Files Anton Shepelev <anton.txt@gmail.com> - 2018-02-25 15:02 +0300
Re: Text Files Ben Bacarisse <ben.usenet@bsb.me.uk> - 2018-02-25 20:12 +0000
csiph-web