Re: error: ambiguous overload for 'operator <<' in ...

[Ulrich Eckhardt]

glen wrote:
>   template<typename C>
>   std::ostream& operator<< (std::ostream& op, const C& cpi )
>   {
>    typename C::const_iterator start( cpi.begin() );
>    typename C::const_iterator end( --(cpi.end() ));
>    typename C::const_iterator iter; 
>    op << "{";
>    for (iter=start;iter!=end; ++iter){
>     op<<*iter<<",";
>    }
>    op<<*iter<<"}";
>    return op;
> };
> 
> The offending lines are the 
>       op<<"{";
> and
>       op<<"}";

Several things:
- You didn't provide a minimal example.
- You didn't provide the errormessage.
- The last semicolon is wrong.
- Your indentation is inconsistent, making it harder for the reader.
- Your code invokes undefined behaviour on an empty container.

> apparently it doesn't know what to do with a simple string

Well, anyways, your operator's signature matches _EVERYTHING_, including a
character literal.

Uli

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