[Boost-users] Re: Tuples and stringstream

CodeLogic wrote:

Hi,

Hi, Let me reorder your message a bit.

I'm trying to use stringstreams in a tuple like

... give me the following error:

c:\.....\include\boost-1_32\boost\tuple\detail\tuple_basic_no_partial_spec.hpp(1 90):

error C2558: class 'std::basic_stringstream<_Elem,_Traits,_Alloc>' : no copy constructor available or copy constructor is declared 'explicit' with [ _Elem=char, _Traits=std::char_traits<char>, _Alloc=std::allocator<char> ]

You can't create a tuple of stringstreams because basic_ios, which is a base class of stringstream, is non copyable. You should be able to create a tuple of references to stringstreams, though.

fstream fin(filename.c_str(), ios_base::in); tuple test; fin>>test;

It's not clear what you're trying to do do here. If I saw this code in isolation, I'd guess you were trying to deserialize a tuple containing three strings.

I'm basically looking for a solution of being able to stream tuples with strings in the them in and out of a file.> Any suggestions will be appreciated.

Do you mean you want to store and retrieve a tuple? You can't use operator>> for this, since it will use whitespace as a separator, in addition to being sensitive to istream field widths. You might try Boost.Serialization, although since I haven't used this library yet I don't know whether there is support for serializing tuples or whether you have to do it yourself. A simpler way would simply be to write the string to a file separated by a character which you know won't appear in any of the strings, if there is such a character.

Thanks !

Jonathan