Comments on freakcode: Collection.IsNullOrEmpty

Yes I know it would make a candidate for and exten...

2008-09-01T10:02:05.142+02:00

Yes I know it would make a candidate for and extension method and I thought about it when I wrote the post but I don't feel comfortable using extension methods that accept null parameters since I feel that it breaks common practice and relaxes the view on calling stuff on objects that might be null.

It's just not obvious enough that you're actually calling a static method and passing in null as the first parameter.

You could also turn this into an extension method:...

2008-09-01T09:26:12.829+02:00

You could also turn this into an extension method:

public static bool IsNullOrEmpty(this ICollection ic)
{
return (ic == null || ic.Count == 0);
}

Then you can write:

var employees = new List<string>() {"Bob", "Alice", "Tom" };
if(employees.IsNullOrEmpty())
{
FireTheirAsses(employees);
}

Which then reads the same regardless of the collection implementing ICollection.

Nice catch, right you are of course, there's reall...

2008-08-30T23:41:47.983+02:00

Nice catch, right you are of course, there's really no need to check for negative values in collections and I've updated the post.

To answer your question though. If you look at the IL generated from the >= statement you'll see that it (as one could expect) calls the clt instrucion (compare less than) and if that succeeds it calls the ceq (check equality) instruction.

I head a fun thought though.. You could just check for Count > int.MinValue =)

As earlier stated, this small helper method rocks....

2008-08-30T20:51:16.344+02:00

As earlier stated, this small helper method rocks. But, I was just wondering; shouldn't it read:

return (ic == null || ic.Count == 0);

Count can't be negative, right? I don't know which of the tests that is performed first ("less than" or "equal to"), but if it starts with "less than", you would save a couple of CPU cycles =)

Cheers! :D