Re: how to use regex library

From	cri@tiac.net (Richard Harter)
Newsgroups	comp.lang.c
Subject	Re: how to use regex library
Date	2011-05-20 01:01 +0000
Message-ID	<4dd5b6a6.17206925@text.giganews.com> (permalink)
References	(6 earlier) <pan.2011.05.19.11.59.30.927000@Owner-PC.com> <pan.2011.05.19.19.12.48.713000@Owner-PC.com> <slrnitarbh.pff.usenet-nospam@guild.seebs.net> <4dd5822c.3772884@text.giganews.com> <slrnitb44f.uvp.usenet-nospam@guild.seebs.net>

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On 19 May 2011 22:06:22 GMT, Seebs <usenet-nospam@seebs.net> wrote:

>On 2011-05-19, Richard Harter <cri@tiac.net> wrote:
>> Because that is a quite reasonable expectation.
>
>Is it?
>
>I can certainly see it being one of the possible outcomes, but I wouldn't
>*expect* it.

I wouldn't expect that you would expect it.  But that doesn't mean it
isn't reasonable.
>
>> Many search
>> facilities operate either operate that way or they have a 'next
>> instance' command.
>
>This is true, but some don't.  And I guess that's the thing; I might
>anticipate the possibility of an interface doing something, but if I
>test it and it doesn't, that's not usually going to be a major source
>of confusion.

I would have thought you would have read the documentation first - I
may be wrong but that seems like a reasonable expectation to me.

>
>In C, if I write sqrt(1), I don't expect to get 1 the first time I call
>it and -1 the second time I call it.

Sqrt is a search function?  

>In general, unless an interface
>is specified otherwise, I expect it to behave the same way every time,
>and nearly all the interfaces that are specified otherwise, we avoid
>like the plague because they're bugs waiting to happen.
>
>*cough*strtok*cough*.

I'm with you.  I expect fgets to return the same line each time I call
it.  :-)

More seriously, there is a difference between "returns the same
result" and "behaves the same way".
>
>> It is misleading to say that computers 'do what
>> you tell them to do'.  Unless you are programming down to the bare
>> iron you don't tell computers what to do - you tell some piece of
>> software what to do.  What that software does is (sometimes) what the
>> programmer who wrote it decided it ought to do.  It is a serious
>> mistake to blame the computer for the design errors of the software
>> creators.
>
>True enough, but in C, you generally have a pretty good bet that something
>will do what it says it does.  If it doesn't say "repeated calls with the
>same arguments will do different things", then they probably won't.  :)


Except when they do.   :-)

Thread

how to use regex library Owner <Owner@Owner-PC.com> - 2011-05-17 23:11 -0400
  Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-18 03:33 +0000
    Re: how to use regex library Owner <Owner@Owner-PC.com> - 2011-05-18 06:41 -0400
      Re: how to use regex library James Kuyper <jameskuyper@verizon.net> - 2011-05-18 08:00 -0400
        Re: how to use regex library Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-18 20:00 +0100
          Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-18 19:44 +0000
            Re: how to use regex library Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 00:43 +0100
              Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-19 00:52 +0000
                Re: how to use regex library Owner <Owner@Owner-PC.com> - 2011-05-18 22:04 -0400
                Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-19 02:21 +0000
                Re: how to use regex library Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 04:04 +0100
                Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-19 03:14 +0000
                Re: how to use regex library Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 12:03 +0100
                Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-19 14:37 +0000
                Re: how to use regex library Geoff <geoff@invalid.invalid> - 2011-05-19 11:29 -0700
                Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-19 19:08 +0000
                Re: how to use regex library Geoff <geoff@invalid.invalid> - 2011-05-19 12:11 -0700
                Re: how to use regex library Kenneth Brody <kenbrody@spamcop.net> - 2011-05-20 12:55 -0400
                Re: how to use regex library Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 04:01 +0100
            Re: how to use regex library cri@tiac.net (Richard Harter) - 2011-05-19 16:02 +0000
              Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-19 16:34 +0000
                Re: how to use regex library Tim Rentsch <txr@alumni.caltech.edu> - 2011-05-19 13:59 -0700
                Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-19 22:06 +0000
                Re: how to use regex library Tim Rentsch <txr@alumni.caltech.edu> - 2011-05-24 02:03 -0700
                Re: how to use regex library Kenneth Brody <kenbrody@spamcop.net> - 2011-05-20 13:14 -0400
                Re: how to use regex library Tim Rentsch <txr@alumni.caltech.edu> - 2011-05-24 02:16 -0700
            Re: how to use regex library Kenneth Brody <kenbrody@spamcop.net> - 2011-05-19 14:37 -0400
          Re: how to use regex library James Kuyper <jameskuyper@verizon.net> - 2011-05-18 19:44 -0400
            Re: how to use regex library Ben Bacarisse <ben.usenet@bsb.me.uk> - 2011-05-19 03:49 +0100
              Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-19 03:03 +0000
                Re: how to use regex library Ike Naar <ike@iceland.freeshell.org> - 2011-05-19 06:48 +0000
                Re: how to use regex library James Kuyper <jameskuyper@verizon.net> - 2011-05-19 05:58 -0400
                Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-19 14:37 +0000
            Re: how to use regex library Kenneth Brody <kenbrody@spamcop.net> - 2011-05-19 14:48 -0400
              Re: how to use regex library Shao Miller <sha0.miller@gmail.com> - 2011-05-19 15:05 -0400
      Re: how to use regex library Mark Bluemel <mark_bluemel@pobox.com> - 2011-05-18 13:36 +0100
        Re: how to use regex library Owner <Owner@Owner-PC.com> - 2011-05-18 13:13 -0400
        Re: how to use regex library Owner <Owner@Owner-PC.com> - 2011-05-18 22:13 -0400
          Re: how to use regex library Mark Bluemel <mark_bluemel@pobox.com> - 2011-05-19 08:55 +0100
            Re: how to use regex library Owner <Owner@Owner-PC.com> - 2011-05-19 07:59 -0400
              Re: how to use regex library Keith Thompson <kst-u@mib.org> - 2011-05-19 08:50 -0700
              Re: how to use regex library Owner <Owner@Owner-PC.com> - 2011-05-19 15:12 -0400
                Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-19 19:40 +0000
                Re: how to use regex library cri@tiac.net (Richard Harter) - 2011-05-19 20:58 +0000
                Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-19 22:06 +0000
                Re: how to use regex library cri@tiac.net (Richard Harter) - 2011-05-20 01:01 +0000
                Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-20 01:57 +0000
                Re: how to use regex library Kenneth Brody <kenbrody@spamcop.net> - 2011-05-20 13:27 -0400
                Re: how to use regex library Kenneth Brody <kenbrody@spamcop.net> - 2011-05-20 13:08 -0400
                Re: how to use regex library Dr Nick <3-nospam@temporary-address.org.uk> - 2011-05-20 18:54 +0100
                Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-20 19:14 +0000
                Re: how to use regex library Dr Nick <3-nospam@temporary-address.org.uk> - 2011-05-21 00:04 +0100
                Re: how to use regex library Kenneth Brody <kenbrody@spamcop.net> - 2011-05-23 12:42 -0400
                Re: how to use regex library Dr Nick <3-nospam@temporary-address.org.uk> - 2011-05-23 20:16 +0100
                Re: how to use regex library cri@tiac.net (Richard Harter) - 2011-05-23 21:16 +0000
                Re: how to use regex library Kenneth Brody <kenbrody@spamcop.net> - 2011-05-24 12:08 -0400
                Re: how to use regex library cri@tiac.net (Richard Harter) - 2011-05-25 05:27 +0000
                Re: how to use regex library Michael Press <rubrum@pacbell.net> - 2011-05-22 21:41 -0700
                Re: how to use regex library cri@tiac.net (Richard Harter) - 2011-05-23 21:33 +0000
      Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-18 16:03 +0000
    Re: how to use regex library Jorgen Grahn <grahn+nntp@snipabacken.se> - 2011-05-18 14:05 +0000
  Re: how to use regex library Owner <Owner@Owner-PC.com> - 2011-05-20 22:06 -0400
    Re: how to use regex library Seebs <usenet-nospam@seebs.net> - 2011-05-21 03:49 +0000
      Re: how to use regex library Owner <Owner@Owner-PC.com> - 2011-05-21 20:25 -0400
    Re: how to use regex library Shao Miller <sha0.miller@gmail.com> - 2011-05-21 13:17 -0500

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