What should I do about “Possible compare of value type with 'null'”?

Question

While writing this method for a custom NUnit Constraint.

    private void AddMatchFailure(string failureName, TExpected expected, TActu         


        

Answer 1

Don't change the code - just ignore the warning. If the type parameter is a non-nullable value type, the comparison will always fail and it'll always call ToString() instead. I don't know whether it's actually JITted away, but I wouldn't be surprised... and this doesn't sound like it's performance-critical code anyway :)

I'd personally leave the warning "on", but ignore it in this particular case - possibly with a comment.

I think I came across the same warning a few times when reimplementing LINQ to Objects.