Working with IComparable.Compare without magic numbers

Question

I really hate working with IComparer - to this day, after years of working with .Net, I still get regularly confused by those 1s and -1s.

Can I somehow replace the Compare result values with some self-explanatory names without having to cast the output integers to something else after every Compare call?

I tried to define an enum like this:

public enum ComparerResult
{
    ALessThanB = -1,
    Equal = 0,
    AGreaterThanB = 1
}

if(comparer.Compare(a, b) == ComparerResult.ALessThanB)

But that of course won't compile without a cast.

This of course also applies to IComparable.CompareTo.

Thanks for your ideas

Answer 1

I prefer this to express less-than:

if (comparer.Compare(a, b) < 0)

This is a nice mnemonic because you use the same operator for comparison with zero as you would between the two operands.

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As Reddog reminded me in the comments, the specification for the interfaces does not require -1 and 1 specifically; it only requires negative and positive results. As such, the logic you're currently using is not guaranteed to work in all cases.