Well that's perfect,
Hi wijnand,
sorry if i am using your name?

I know bits and peace about template programming, if you don't mind
can you give some advice
like which book to read for good template programming. It would be
very ful if you can
give link to any of the articles authored by you.

On Oct 16, 7:31 pm, wijnand <wijnandsuij...@gmail.com> wrote:
> Is this something you can use?
>
> #include <iostream>
> #include <string>
>
> template <class T>
> struct ToString;
> // keep this empty to emit a compile time error
> // when it doesn't have a associated string
>
> // Define the format specifiers of the basic types
> #define DEF0TYPE( type, str ) \
> template <> \
> struct ToString< type > \
> { static std::string value() { return str; } \
> };
>
> DEF0TYPE( int, "%d" )
> DEF0TYPE( double, "%f" )
> DEF0TYPE( char *, "%s" )
> DEF0TYPE( const char *, "%s" )
> DEF0TYPE( float, "%f")
> DEF0TYPE( char, "%c")
> /* andsoforth... */
> #undef DEF0TYPE
>
> // define the format string of a nullary function
> template <class Return>
> struct ToString< Return (*) () >
> {
> static std::string value() { return "%s()"; }
>
> };
>
> // unary functions
> template <class Return, class T >
> struct ToString< Return (*) ( T ) >
> {
> static std::string value() { return std::string("%s(") +
> ToString<T> :: value() + ")"; }
>
> };
>
> // binary functions
> template <class Return, class T, class U >
> struct ToString< Return (*) ( T , U ) >
> {
> static std::string value() { return std::string("%s(") +
> ToString<T> :: value() + ", " + ToString<U>::value() + ")"; }
>
> };
>
> // ternary functions
> template <class Return, class T, class U, class V >
> struct ToString< Return (*) ( T , U, V ) >
> {
> static std::string value() { return std::string("%s(") +
> ToString<T> :: value() + ", " + ToString<U>::value() + ", " +
> ToString<V>::value() + ")"; }
>
> };
>
> // and so on
>
> // a er function, which provides a bit nicer syntax
> template <class T>
> std::string toString( T )
> {
> return ToString<T> :: value();
>
> }
>
> // two functions
> void function1( int a, double b) {}
> void function2( double x, double y, char * string) {}
>
> int main()
> {
> std::cout << "format string for the main function: " <<
> toString( main ) << std::endl;
> std::cout << "format string of 'function1' " <<
> toString( function1 ) << std::endl;
> std::cout << "format stirng of 'function2' " << toString( function2)
> << std::endl;
> return 0;
>
> }
>
> This gives as output
> format string for the main function: %s()
> format string of 'function1' %s(%d, %f)
> format stirng of 'function2' %s(%f, %f, %s)
>
> regard,
> Wijnand Suijlen