// comment line below if bool is a built-in type

#ifndef _LVPSTRING_H_
#define _LVPSTRING_H_

#include <iostream.h>
#include "cvclibdef.h"


// *******************************************************************
//  Last Revised: 11/24/98  corrected specification comments
//
//  APCS string class
//
//  string class consistent with a subset of the standard C++ string class
//  as defined in the draft ANSI standard
// *******************************************************************

extern const int npos;  // used to indicate not a position in the string

class String
{
  public:

  // constructors/destructor

	 String( );                         // construct empty string ""
	 String( const char * s );          // construct from string literal
	 String( const String & str );      // copy constructor
	 ~String( );                        // destructor

  // assignment

	 const String & operator = ( const String & str ); // assign str
	 const String & operator = ( const char * s );       // assign s
	 const String & operator = ( char ch );              // assign ch

  // accessors

	 int    length( )                  const;    // number of chars
	 int    find( const String & str ) const;  // index of first occurrence of str
	 int    find( char ch )            const;    // index of first occurrence of ch
	 String substr( int pos, int len ) const;    // substring of len chars
																// starting at pos
	 const char * c_str( )             const;    // explicit conversion to char *

  // indexing

	 char   operator[ ]( int k )       const;    // range-checked indexing
	 char & operator[ ]( int k );                // range-checked indexing

  // modifiers

	 const String & operator += ( const String & str );// append str
	 const String & operator += ( char ch );            // append char


  private:
		int myLength;                     // length of string (# of characters)
		int myCapacity;                   // capacity of string
		char * myCstring;                 // storage for characters
};

// The following free (non-member) functions operate on strings
//
// I/O functions

ostream & operator << ( ostream & os, const String & str );
istream & operator >> ( istream & is, String & str );
istream & getline( istream & is, String & str );

// comparison operators:

bool operator == ( const String & lhs, const String & rhs );
bool operator != ( const String & lhs, const String & rhs );
bool operator <  ( const String & lhs, const String & rhs );
bool operator <= ( const String & lhs, const String & rhs );
bool operator >  ( const String & lhs, const String & rhs );
bool operator >= ( const String & lhs, const String & rhs );

// concatenation operator +

String operator + ( const String & lhs, const String & rhs );
String operator + ( char ch, const String & str );
String operator + ( const String & str, char ch );


#endif