row_1.h

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// ============================================================================
// Project:     Deductive Database
// Filename:    row_1.h
// Purpose:     Tuple/Table Row with one integer column.
// Last Change: 04.08.2017
// Language:    C++
// EMail:       brass@informatik.uni-halle.de
// WWW:         http://www.informatik.uni-halle.de/~brass/
// Address:     Feldschloesschen 15, D-06120 Halle (Saale), GERMANY
// Copyright:   (c) 2015-2017 by Stefan Brass
// License:     See file "LICENSE" for copying conditions.
// Note:        There is no warranty at all - this code may contain bugs.
// ============================================================================


//=============================================================================
// Include File Frame:
//=============================================================================

#ifndef ROW_1_INCLUDED
#define ROW_1_INCLUDED

//=============================================================================
// Used Types and Macros:
//=============================================================================

#ifndef VER_INCLUDED
#include "../base/ver.h"
#endif

#ifndef STR_INCLUDED
#include "../base/str.h"
#endif

#ifndef CHECK_INCLUDED
#include "../base/check.h"
#endif


//=============================================================================
// Private Constants:
//=============================================================================

//-----------------------------------------------------------------------------
// ROW_1_MAGIC: Magic number (identifies objects of this class).
//-----------------------------------------------------------------------------

static const long ROW_1_MAGIC = 0x525F310AL;    // 'R_1\n'

//=============================================================================
// Class for Relation with two integer columns, no index:
//=============================================================================

class row_1_c {
        public:

//-----------------------------------------------------------------------------
// Constants:
//-----------------------------------------------------------------------------

        static const int NUM_COLS = 1;

//-----------------------------------------------------------------------------
// Constructor, Destructor:
//-----------------------------------------------------------------------------

        // Constructor:
        row_1_c(int col1) : C1(col1) {

                // Set Magic number:
                CHECK_CODE(Magic = ROW_1_MAGIC);
        }

        // Destructor:
        ~row_1_c() {
                // Check this object:
                CHECK_VALID("row_1_c::destructor");

                // Make this object invalid:
                CHECK_CODE(Magic = 0);
        }

        // Copy-constructor:
        row_1_c(const row_1_c& row) : C1(row.C1) {

                // Set Magic number:
                CHECK_CODE(Magic = ROW_1_MAGIC);
        }

//-----------------------------------------------------------------------------
// (Object) Methods:
//-----------------------------------------------------------------------------

        // c1: Get value of first (and only) column.
        int c1() const {
                // Check this object:
                CHECK_VALID("row_1_c::c1");

                // Return value of column 1:
                return C1;
        }

        // hash: Compute a hash value.
        int hash() const {
                // Check this object:
                CHECK_VALID("row_1_c::hash");

                // There is only a single integer, this is used as hash value:
                if(C1 >= 0)
                        return C1;
                else {
                        int hash_val = -(C1+1);
                        CHECK(hash_val >= 0,
                                        "row_1_c::hash: Value still negative");
                        return hash_val;
                }
        }


        // ==: equality test.
        bool operator==(const row_1_c& other) const {
                // Check this object:
                CHECK_VALID("row_1_c::==");

                // Objects are equal if they have the same value in C1:
                return C1 == other.C1;
        }

        // =: Assignment Operator.
        row_1_c& operator=(const row_1_c& other) {
                // Copy data value:
                C1 = other.C1;

                // Set Magic number:
                CHECK_CODE(Magic = ROW_1_MAGIC);

                // Return this object (standard interface of assignment op):
                return *this;
        }

        // Create a string representation in a given buffer:
        void to_string(char *buf, int buf_len) const;
        
//-----------------------------------------------------------------------------
// Debugging Support:
//-----------------------------------------------------------------------------

#if     VER_DEBUG
        public:
        // Integrity check:
        str_t   check() const;

        private:
        // Magic number (identifies objects of this class for debugging).
        long    Magic;          // Must be "ROW_1_MAGIC".
#endif

#if     VER_DUMP
        public:
        // Display data structure:
        void dump(str_t headline = STR_NULL) const;
#endif


//-----------------------------------------------------------------------------
// Private Object Members:
//-----------------------------------------------------------------------------

        private:

        // Column value:
        int C1;

//=============================================================================
// End of Class:
//=============================================================================

};

//-----------------------------------------------------------------------------
// Define pointer type:
//-----------------------------------------------------------------------------

typedef row_1_c *row_1_t;

//-----------------------------------------------------------------------------
// Define null pointer:
//-----------------------------------------------------------------------------

#define ROW_1_NULL (static_cast<row_1_t>(0))

//=============================================================================
// End of Include File:
//=============================================================================

#endif