Operator overloading

Code:

---


bool retval;
        if( _first < p._first )
                  retval =  true;
        if(_first > p._first)
                retval = false;
       
        if(_first == p._first)
                if(_i1 == p._i1)
                        if(_i2  == p._i2)
            retval =  false;
       
       
        if(_i1 < p._i1)
                  retval =  true;
        if(_i1 > p._i1)
                  retval = false;
       
         
          if(_i2 <p._i2)
                  retval =  true;
          if(_i2 >p._i2)
                  retval = false;
       
         

        return retval;

---

I tried this and it seems to work fine now.... I need to do proper testing before i could say hurrahhhhhh!

Thank you Lindley!

Hmm, that doesn't seem quite right to me.

Code:

---

        if( _first < p._first )
                return true;
        if(_first > p._first)
                return false;
        if(_i1 < p._i1)
                return true;
        if(_i1 > p._i1)
                return false;
        return _i2 <p._i2;

---

This is different in the sense that it will *always* make its decision on the earliest possible evidence. Your code might find _first < p._first and set retval to true, but then change its mind when it finds that _i2 > p._i2 and actually return false.

ok, if i understand you correctly, then instead of setting a variable value true or false, return it. In your code, you haven't used the ==, i believe that part of my code is right?

Code:

---


        if( _first < p._first )
                  return  true;
        if(_first > p._first)
                return false;
       
        if(_first == p._first)
                if(_i1 == p._i1)
                        if(_i2  == p._i2)
            return  false;
       
       
        if(_i1 < p._i1)
                  return  true;
        if(_i1 > p._i1)
                  return false;
       
         
          if(_i2 <p._i2)
                  return  true;
          if(_i2 >p._i2)
                  return false;

---

Quote:

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Originally Posted by rachelason

ok, if i understand you correctly, then instead of setting a variable value true or false, return it. In your code, you haven't used the ==, i believe that part of my code is right?

---

I think you should write down on a piece of paper when given two of your objects, what exactly makes one object less than the other (not in C++, but in English). In this, you must make sure that your definition of "less than" is consistent, regardless of the two objects given to you (this is the strict weak ordering).

Then and only then should you now translate what you have on paper to C++ code. Trying to implement "less than" in C++ code when you haven't solidly come up with the definitive description of what is "less than" is not the correct approach.

Regards,

Paul McKenzie

Quote:

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Originally Posted by rachelason

In your code, you haven't used the ==, i believe that part of my code is right?

---

Correct, but unnecessary: that case is already covered by my code. Examine it step by step assuming equal inputs to see that.

You have some "blocks"...each block is Red, Green or Blue (single monochromatic color).

1) Remove all the Red Blocks
2) Remove all the Greeen Blocks
3) Check that all the remaing blocks are Blue.

#3 is obviously redundant. The same is true for checking conditions that are guaranteed to be true by prior tests (and the associated EXITING of the return statement).

Make Sense??