Re: [boost] Re: Review of Daryle Walker's "More IO" library begins today, August 21, 2004.

From: Darren Cook (darren_at_[hidden])
Date: 2004-08-24 18:10:06

>>So, what I want is something to say insert a carriage-return before
>> calling operator<<, e.g.
>>   SMART_ASSERT( this==that )(prefix_cr(brd))(this)(that);
> 
> Why not something like:
 >  ...

Thanks! That worked.

 > Is there a more general version of the problem?

I don't know - I cannot remember needing to prefix anything other than a 
carriage-return.

I need to indent a 2d output sometimes (e.g. in trace logs to show the depth 
of recursion) but that requires a prefix to each line so is a different kind 
of problem.

Darren

---------------------------------------
template<typename T>
struct cr_prefixed {
     cr_prefixed(T& t) : t(t) { }
     void print(std::ostream& out) const
     {
         out << "\n" << t;
     }
     T& t;
};

template<typename T>
std::ostream& operator<<(std::ostream& out, const cr_prefixed<T>& p)
{
     p.print(out);
     return out;
}

template<typename T>
cr_prefixed<T> prefix_cr(T& t) { return cr_prefixed<T>(t); }