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0 pointsgjulianm13y ago0 comments

Well, you could substitute that for

     if(Int.CanParse(s))
     {
         i = Int.Parse(s);
         // OK things.
     }
     else
     {
        // Not ok.
     }

but it also be weird in Java because Parse throws and exception, so you'd have to either write an empty catch block or declare the method with a throw clause, event though it actually doesn't throw anything.

0 comments

Someone13y ago

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;

mercurial13y ago

You could have a method returning a nullable Integer.

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