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Groups > comp.lang.c++ > #88742
| From | Muttley@dastardlyhq.com |
|---|---|
| Newsgroups | comp.lang.c++ |
| Subject | Re: A string pointer to a static or dynamic string : how to free the |
| Date | 2023-01-23 10:14 +0000 |
| Organization | Aioe.org NNTP Server |
| Message-ID | <tqlmn3$7so$1@gioia.aioe.org> (permalink) |
| References | (1 earlier) <tqgtgk$2kndm$1@dont-email.me> <tqh3d7$376$1@gioia.aioe.org> <tqha4b$2mq2c$1@dont-email.me> <tqljqs$s93$1@gioia.aioe.org> <tqlmgs$3io52$1@dont-email.me> |
On Mon, 23 Jan 2023 12:11:40 +0200
Paavo Helde <eesnimi@osa.pri.ee> wrote:
>23.01.2023 11:25 Muttley@dastardlyhq.com kirjutas:
>> On Sat, 21 Jan 2023 20:15:39 +0200
>> Paavo Helde <eesnimi@osa.pri.ee> wrote:
>>> 21.01.2023 18:20 Muttley@dastardlyhq.com kirjutas:
>>>> On Sat, 21 Jan 2023 16:40:20 +0200
>>>> Paavo Helde <eesnimi@osa.pri.ee> wrote:
>>>>> 21.01.2023 16:28 R.Wieser kirjutas:
>>>>>> Hello all,
>>>>>>
>>>>>> I'm a rather newbie to C++ programming who is trying figure out how to
>deal
>>>
>>>>>> with string pointers - or rather, with what they point at.
>>>>>>
>>>>>> Case in point :
>>>>>>
>>>>>> char* message = "hello world";
>>>>>> char* message = strdup("hello world");
>>>>>>
>>>>>> I can user either of those in a function and return the pointer, and the
>>>>>> caller will be none-the-wiser which form (the static or dymnamic string)
>it
>>>
>>>>>> gets.
>>>>>
>>>>> This is C++, so just return a std::string from your function, and forget
>>>>> everything about C-style strings, malloc, free and strdup. Good riddance!
>>>>
>>>> Unless you want to parse the string which may involve chopping it about.
>Then
>>>
>>>> its simpler to use a C string and pointers rather than mess about with
>>>> inefficient substr() etc.
>>>
>>> If you want to speed up substring processing, then there is
>>> std::string_view for you. As fast as plain pointers and much cleaner.
>>
>> Not really. This is fast, simple and clear:
>>
>> for(p=str;*p;)
>> {
>> switch(*p)
>> {
>> case '[':
>> p = parseList(p+1);
>> break;
>> case '{':
>> p = parseBlock(p+1);
>> break;
>> case '(':
>> p = parseArray(p+1);
>> break;
>> default:
>> <do something else>
>> ++p;
>> }
>> }
>>
>> Not sure how using indexes and substrings would improve it.
>
>This looks like it either assumes the string is syntactically correct
>(all parens are balanced correctly) or the parsed string is terminated
>by a null byte. So when parsing a substring of some larger text or
Or the given function works up to the matching close bracket and returns
the pointer to that + 1. In a real parser this would be in a recursive function
because of nested blocks/lists etc.
>binary file I would need to copy it out and append a null byte, just to
>be sure my error detection works properly.
>
>When using string_view, you always know how long your to-be-processed
>piece is, so you don't need to make pointless copies just to know where
Your to-be-processed piece will be the entire program/text to be parsed at
the start.
>to stop processing. With raw pointers, you would need to pass a separate
>end pointer, which would make the interfaces more complex.
I think we can assume you've never written a parser and leave it at that.
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A string pointer to a static or dynamic string : how to free the dynamic one ? "R.Wieser" <address@not.available> - 2023-01-21 15:28 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Paavo Helde <eesnimi@osa.pri.ee> - 2023-01-21 16:40 +0200
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Bonita Montero <Bonita.Montero@gmail.com> - 2023-01-21 15:57 +0100
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-21 16:20 +0000
Re: A string pointer to a static or dynamic string : how to free the Paavo Helde <eesnimi@osa.pri.ee> - 2023-01-21 20:15 +0200
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-23 09:25 +0000
Re: A string pointer to a static or dynamic string : how to free the Paavo Helde <eesnimi@osa.pri.ee> - 2023-01-23 12:11 +0200
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-23 10:14 +0000
Re: A string pointer to a static or dynamic string : how to free the Paavo Helde <eesnimi@osa.pri.ee> - 2023-01-23 14:14 +0200
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-23 12:27 +0000
Re: A string pointer to a static or dynamic string : how to free the Paavo Helde <eesnimi@osa.pri.ee> - 2023-01-23 17:56 +0200
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-23 16:11 +0000
Re: A string pointer to a static or dynamic string : how to free the Paavo Helde <eesnimi@osa.pri.ee> - 2023-01-23 18:58 +0200
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-23 17:18 +0000
Re: A string pointer to a static or dynamic string : how to free the Paavo Helde <eesnimi@osa.pri.ee> - 2023-01-23 19:49 +0200
Re: A string pointer to a static or dynamic string : how to free the Cholo Lennon <chololennon@hotmail.com> - 2023-01-23 16:44 -0300
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-24 17:05 +0000
Re: A string pointer to a static or dynamic string : how to free the Bonita Montero <Bonita.Montero@gmail.com> - 2023-01-21 19:30 +0100
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-23 09:30 +0000
Re: A string pointer to a static or dynamic string : how to free the Bonita Montero <Bonita.Montero@gmail.com> - 2023-01-23 13:53 +0100
Re: A string pointer to a static or dynamic string : how to free the scott@slp53.sl.home (Scott Lurndal) - 2023-01-23 14:46 +0000
Re: A string pointer to a static or dynamic string : how to free the Bonita Montero <Bonita.Montero@gmail.com> - 2023-01-23 16:48 +0100
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-23 16:09 +0000
Re: A string pointer to a static or dynamic string : how to free the Bonita Montero <Bonita.Montero@gmail.com> - 2023-01-23 17:13 +0100
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-23 16:20 +0000
Re: A string pointer to a static or dynamic string : how to free the Bonita Montero <Bonita.Montero@gmail.com> - 2023-01-23 17:25 +0100
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-23 16:37 +0000
Re: A string pointer to a static or dynamic string : how to free the Bonita Montero <Bonita.Montero@gmail.com> - 2023-01-23 17:40 +0100
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-23 17:00 +0000
Re: A string pointer to a static or dynamic string : how to free the Wuns Haerst <Wuns.Haerst@wurstfabrik.at> - 2023-01-23 20:07 +0100
Re: A string pointer to a static or dynamic string : how to free the scott@slp53.sl.home (Scott Lurndal) - 2023-01-23 17:30 +0000
Re: A string pointer to a static or dynamic string : how to free the Bonita Montero <Bonita.Montero@gmail.com> - 2023-01-23 18:39 +0100
Re: A string pointer to a static or dynamic string : how to free the "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2023-01-23 08:40 -0800
Re: A string pointer to a static or dynamic string : how to free the Muttley@dastardlyhq.com - 2023-01-23 17:02 +0000
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Juha Nieminen <nospam@thanks.invalid> - 2023-01-23 06:34 +0000
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Paavo Helde <eesnimi@osa.pri.ee> - 2023-01-23 12:49 +0200
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Juha Nieminen <nospam@thanks.invalid> - 2023-01-23 11:51 +0000
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2023-01-23 04:05 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? wij <wyniijj5@gmail.com> - 2023-01-23 04:45 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Richard Damon <Richard@Damon-Family.org> - 2023-01-21 10:13 -0500
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "R.Wieser" <address@not.available> - 2023-01-21 17:53 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2023-01-21 08:04 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-01-21 16:54 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? jak <nospam@please.ty> - 2023-01-22 10:46 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2023-01-22 05:20 -0500
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? jak <nospam@please.ty> - 2023-01-22 12:17 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Bo Persson <bo@bo-persson.se> - 2023-01-22 12:29 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? jak <nospam@please.ty> - 2023-01-22 13:23 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Paavo Helde <eesnimi@osa.pri.ee> - 2023-01-22 14:53 +0200
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? jak <nospam@please.ty> - 2023-01-22 19:04 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? jak <nospam@please.ty> - 2023-01-22 19:16 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? David Brown <david.brown@hesbynett.no> - 2023-01-23 09:46 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? jak <nospam@please.ty> - 2023-01-23 13:22 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? David Brown <david.brown@hesbynett.no> - 2023-01-23 14:42 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2023-01-23 06:15 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2023-01-23 08:22 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? David Brown <david.brown@hesbynett.no> - 2023-01-23 18:02 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2023-01-23 11:14 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2023-01-23 11:38 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-01-23 13:26 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Richard Damon <Richard@Damon-Family.org> - 2023-01-22 13:24 -0500
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-01-22 11:00 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2023-01-22 15:39 -0500
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2023-01-22 15:28 -0500
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "R.Wieser" <address@not.available> - 2023-01-22 12:27 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Öö Tiib <ootiib@hot.ee> - 2023-01-22 03:42 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? David Brown <david.brown@hesbynett.no> - 2023-01-22 15:31 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "R.Wieser" <address@not.available> - 2023-01-22 15:40 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Richard Damon <Richard@Damon-Family.org> - 2023-01-22 13:24 -0500
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2023-01-22 11:46 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? David Brown <david.brown@hesbynett.no> - 2023-01-23 10:24 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? scott@slp53.sl.home (Scott Lurndal) - 2023-01-23 14:44 +0000
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2023-01-23 07:34 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? David Brown <david.brown@hesbynett.no> - 2023-01-23 18:05 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Malcolm McLean <malcolm.arthur.mclean@gmail.com> - 2023-01-23 09:37 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? scott@slp53.sl.home (Scott Lurndal) - 2023-01-23 17:37 +0000
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "R.Wieser" <address@not.available> - 2023-01-22 21:16 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-01-22 13:07 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "R.Wieser" <address@not.available> - 2023-01-23 08:33 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2023-01-23 04:00 -0500
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-01-23 12:34 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-02-02 06:43 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "james...@alumni.caltech.edu" <jameskuyper@alumni.caltech.edu> - 2023-02-02 16:36 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Tim Rentsch <tr.17687@z991.linuxsc.com> - 2023-02-02 17:38 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2023-01-22 10:57 -0800
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "R.Wieser" <address@not.available> - 2023-01-22 21:23 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2023-01-22 15:47 -0500
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "R.Wieser" <address@not.available> - 2023-01-23 08:04 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? James Kuyper <jameskuyper@alumni.caltech.edu> - 2023-01-23 04:13 -0500
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? David Brown <david.brown@hesbynett.no> - 2023-01-23 10:33 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Mike Terry <news.dead.person.stones@darjeeling.plus.com> - 2023-01-21 18:29 +0000
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "R.Wieser" <address@not.available> - 2023-01-21 20:09 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Richard Damon <Richard@Damon-Family.org> - 2023-01-21 16:32 -0500
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "R.Wieser" <address@not.available> - 2023-01-22 10:52 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Mike Terry <news.dead.person.stones@darjeeling.plus.com> - 2023-01-21 22:10 +0000
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "R.Wieser" <address@not.available> - 2023-01-22 11:56 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Paavo Helde <eesnimi@osa.pri.ee> - 2023-01-22 14:31 +0200
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? "R.Wieser" <address@not.available> - 2023-01-22 15:57 +0100
Re: A string pointer to a static or dynamic string : how to free the dynamic one ? Juha Nieminen <nospam@thanks.invalid> - 2023-01-23 06:40 +0000
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