//  Simple String class
//  -------------------

#ifndef SIMPLE_STRING
#define SIMPLE_STRING const SimpleString
#include <string.h>

//  This class provides a minimal character-string capability suitable
//  for classroom or textbook examples not concerned with techniques
//  of string class design or use.

//  Its main purpose is to support string-valued functions. It provides
//  concatenation but no substring or parsing functions. 

//  For more complete or more efiicient character string classes, see
//  std::string or the IDI library classes Dstring, Vstring, and Cstring.

class SimpleString {
      
    char* value;                    //  Internal representation is 
    int   size;                     //    null-terminated array of char

public:
    SimpleString (const char *const arg = "") 
         {size = strlen(arg);
          value = new char[1+size]; strcpy(value,arg);
         }
    SimpleString (const char x) 
         {size = 1;
          value = new char[2]; value[0] = x; value[1] = '\0';
         }
    SimpleString (SIMPLE_STRING& x)
         {size = x.size;
          value = new char[1+x.size]; strcpy(value,x.value);
         }
    ~SimpleString() {delete value;}

  SimpleString& operator=(SIMPLE_STRING& rs)
     {if (size != rs.size)                //  Check for reallocation needed
        {delete value; value = new char[1+rs.size];} 
      strcpy(value,rs.value);
      return *this;
     }

  friend SimpleString operator+(SIMPLE_STRING ls, SIMPLE_STRING rs)
     {SimpleString result;
      result.size  = ls.size + rs.size;
      delete result.value; result.value = new char[1 + result.size];  
      strcpy(result.value,ls.value);
      strcat(result.value,rs.value);
      return result;
     }     

  static SimpleString toString(INT N, SHORT base)
     {int n = abs(N);
      static const char digitTable[17] = "0123456789ABCDEF";  
      char result[17]; result[16] = '\0';
      int posn = 15;
      do {result[posn--] = digitTable[n%base];
          n /= base;
         } while(n > 0);
      return result+posn+1;
     }    

 friend ostream& operator<<(ostream&ls, SIMPLE_STRING& rs)
    {return ls << rs.value;}  

};

#endif