Re: [boost] boost::lexical_cast<bool>("true");

From: tslettebo_at_[hidden]
Date: 2003-05-06 09:41:02

> From: Markus Werle <numerical.simulation_at_[hidden]>
> 
> The feature mentioned in the subject is missing in boost.
> (actually it throws)
> I propose adding something simmilar to the (incomplete) stuff below.
> 
> template <typename Source>
> class lexical_stream_common_stuff<bool, Source>

This could be a possibility. Rather than testing for the strings "true" and "false" (which wouldn't respect locale), it may be better to set the ios_base "boolalpha" flag, which reads and writes bool as "true" and "false" (or whatever is set for the locale).

However, the question is that some users may want to read/write "0" and "1", instead.

This has the same problem as other stream configuration, such as setting the number base, etc.

>   bool assign_from(const std::string& s)
>   {
>     if ("true" == s) 
>       {
>         result_ = true;
>         return true;
>       } 
>     if ("false" == s) 
>       {
>         result_ = false;
>         return true;
>       } 
>     return false;
>   }

<snip>

> template<>
> class lexical_stream<bool, const char*>
>   : public lexical_stream_common_stuff<bool, const char*>

Regards,

Terje