[Someone]

That either is inefficient (you end up parsing each number twice) or requires the compiler to have deep knowledge of the standard library.

Similarly, C# has TryGet where in Java, you need a containsKey/get combo, or have to assume your collections do not store nulls.

I do think C# could do better, though. Neither C# nor Java have the equivalent of "insert ... on duplicate key ..." for collections. You now have to do:

   items.TryGet( key, out value);
   items[key] = value + 1;

In C++, that would just be:

   items[key] += 1;

[mercurial]

You could have a method returning a nullable Integer.