Re: string to wstring problems
Gennaro Prota wrote:
On 26 Apr 2007 06:12:41 -0700, James Kanze <james.kanze@gmail.com>
wrote:
2. It is acceptable that there is no conversion from
wstring to string, but, Why there is no conversion
(wstring::wstring(string )) from string to wstring?
Because for some stupid reason, they're both instantiations of a
template, and there is no generic solution.
Also, of course, because the conversion would have to be locale
specific. (But that doesn't explain why there is no
string::toWString( locale const& ) function. That has to be
chalked up to the design error of making std::string a
template.)
Do you really mean that it should be a member of std::string? I'd
rather go for a namespace scope function:
std::wstring widen( const std::string &,
const std::locale & = std::locale() );
Both ways can be made to work. I don't think it really changes
the issues. We have two classes, std::string and std::wstring,
which really require a slightly different interface. And of
course, in practice, you can't really instantiate basic_string
for anything else, and expect it to work.
There's also an interesting question: if std::string is supposed
to represent text, shouldn't it know in what encoding it is?
(This would very strongly argue for a member, of course.) But
of course, if std::string is supposed to represent text, we also
get a number of awkward questions with regards to multi-byte
characters.
--
James Kanze (GABI Software) email:james.kanze@gmail.com
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