Re: std::basic_string<> contiguous data?

From:
"Alf P. Steinbach" <alfps@start.no>
Newsgroups:
comp.lang.c++.moderated
Date:
16 Jan 2007 10:53:33 -0500
Message-ID:
<513q2mF1hk909U1@mid.individual.net>
* Adam White:

I've been writing a NetString class for network transmissions, which has
been internally implemented using a std::string.

To read data into the NetString from a network socket, I'd planned to
pre-allocate a large std::string (to use as a buffer), then slurp data
directly from the socket into the string via pointer indirection or by
using the std::string::data() array.

But is std::basic_string<>'s data guaranteed to be in a contiguous array?
I believe that TR1 clarified the intention that std::vector<> data be
stored contiguously - is that also true of std::basic_string<> ?


As Howard Hinnant remarked else-thread, and as I've mentioned in an
earlier thread in this group, yes in practice: for all widely used
compilers, and slated for adoption in C++0x standard, voted in by the
library working group early this year.

I'm repeating and elaborating on this because follow-ups after Howard's
article have seemingly ignored the fact that only for the purpose of
writing an academic article or book on what the current standard
formally guarantees, ignoring actual compilers and the next standard, is
there any point in allowing the possibility of a non-contiguous buffer.

You're OK with assuming contigous string buffer storage.

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