StrSetCar()

         Modifies a character into a string

    Syntax:

         StrSetCar( cString, nPos, nChar ) -> cNewString

         cString : The string to treat
         nPos    : The string position to act with
         nChar   : The new character of the given position

    Description:

         Modifies a string specified position and returns the new string.
         This function, in conjunction with StrSetCar() may be very
         usefull when a string want to be treated in C style as if they
         were character arrays.

    Return:

         The modified string.

    Example:

         ? StrSetCar ( "Hola mundo", 1, 32 )   //  " ola mundo"
         ? StrSetCar ( "Hola mundo", 0, 35 )   //  "Hola mundo"
         ? StrSetCar ( "Hola mundo", 7, 85 )   //  "Hola mUndo"