Re: [boost] Review Request: Introduction of boost::string namespace, and string-conversion functions

Subject: Re: [boost] Review Request: Introduction of boost::string namespace, and string-conversion functions
From: Anders Dalvander (boost_at_[hidden])
Date: 2009-02-14 04:37:37

On Fri, Feb 13, 2009 at 07:15 +1000, Vladimir Batov 
<batov_at_[hidden]> wrote:

 >> 2. The name of the namespace.
 >>
 >> People largely seem content with "boost::string".

I think that is a pretty bold statement as your proposal for 
boost::string was initially posted merely 26 hours earlier.

Perhaps this library should be bundled with the Boost String Algorithms 
Library, and reside in the boost::algorithm namespace.

 >> 3. Naming of the conversion functions.
 >>
 >> The "to/from/is" set seems to sit well with the majority of people.

I really like the compactness of to/from/is, but something about it 
feels strange. It feels a bit backward as boost::string::to converts 
from a string, and boost::string::from converts to a string.

Perhaps parse and to_string (or construct).

namespace bsa = boost::algorithm; // or boost::string, or 
boost::convert, or boost::text, or boost.

int i_from_s = bsa::parse<int>(s);
std::string s_from_i = bsa::to_string<std::string>(i);

 >> 8. Throw/No-Throw Behavior.
 >>
 >> You might have noticed that the interface above *never* throws 
anything on
failure.

 >> >> template<class T, class String>
 >> >> boost::string::value<T>
 >> >> boost::string::to(String const&, T const& =T()) throw();

 >> >> template<class T>
 >> >> boost::string::value<std::string>
 >> >> boost::string::from(T const&) throw();

I don't think it is a good idea to have the nothrow exception 
specification on either boost::string::from nor boost::string::to as the 
underlying mechanism (iostreams I would believe) or copy-construction of 
T or construction of String could throw exceptions. Nothrow simply 
cannot be guaranteed.

Regards,
Anders Dalvander