string class: Using template constructor

[HairyDave]

I am using the string class in VC++ 6. I am attempting to use the template class constructor:

template <class InIt>
basic_string(InIt first, InIt last, const A& al = A());

However, when I attempt to construct a string using this I get errors about how there are no overloaded versions acceptable - or that it cannot convert from iterator to whatever type it feels like!

How can I use this templated class constructor?

Thanks

HD

[parksie]

You can only use basic_string for char or wchar_t, unfortunately...

[HairyDave]

Hmm. I don't mean to question you, but the MSDN library documents a templated constructor that takes an initial point of an iterator, and a final point of an iterator (and the thing itself). It then 'should' give back a basic_string.

Have you heard of this before and have found that it doesn't work? I'd like to know of any information you have on the subject.

Although I've been using C and C++ for years now, I'm more of a C programmer and so the string class is a bit unfamiliar.

Thanks for any information

HD

[twanvl]

Unfortunatly VC6 doesn't support member template functions:

MSDN:
In this implementation, if a translator does not support member template functions, the template:

template <class InIt>
    basic_string(InIt first, InIt last, const A& al = A());

is replaced by:

basic_string(const_iterator first, const_iterator last,
    const A& al = A());

The only solutions I can think of are:
1. Don't use VC6
2. first construct an empty string, then use std::copy(first,last,out)

[CornedBee]

Originally posted by twanvl
Unfortunatly VC6 doesn't support member template functions:


The only solutions I can think of are:
1. Don't use VC6
2. first construct an empty string, then use std::copy(first,last,out)

Unfortunatly the same restriction applies for std::copy.

If you ever choose to use a good compiler (gcc, VC++7, in that order ) you would do for example

list<wchar_t> ll;
ll.push_back(L'H');
ll.push_back(L'e');
ll.push_back(L'l');
ll.push_back(L'l');
ll.push_back(L'o');

basic_string<wchar_t> str(ll.begin(), ll.end());
wcout << str << endl;

which would output
Hello

You can only use containers that contain the same element type as the string, so if you use string ( = basic_string<char>) you can only copy from <char> containers. If you use wstring ( = basic_string<wchar_t>) you can only use <wchar_t> containers (like list<wchar_t>)

[parksie]

/me has something going at the back of his mind that you can use iterator adapters to do a locale-conversion from wchar_t to char inline

[CornedBee]

Sounds good. Do it.

[parksie]

If I ever get time

So far most of my programming-related projects are on hold while I try and get my (real) work together