Over in WebKit-land there's some disagreement about WebIDL method overload resolution, specifically around passing null, arrays (T[]) and the concept of Nullable.
Here's an example where we're just not sure what the WebIDL spec dictates: void f(float[] x); // overload A void f(DOMString x); // overload B WebIDL itself, of course, doesn't dictate how matching and dispatching should be implemented; it instead defines whether types are distinguishable. The implication is that an IDL that defines methods with signatures that are not distinguishable is invalid, so it's a non-issue in terms of the spec. So rephrasing the question: are the above types distinguishable? And if so, which would be expected to handle the call: f(null); Several interpretations and hence outcomes occur to us, hopefully presented without indicating my particular bias: (1) T[] is inherently Nullable (i.e. T[] === T[]?), DOMString is not, overload A would be invoked with a null argument and the implementation is expected to handle this case (2) T[] accepts null but the IDL type to ECMAScript conversion rules produce an empty array; overload A is invoked with an empty float array (3) T[] does not match null, but as null is an ECMAScript primitive value it is run through ToString() and hence overload B is invoked with DOMString "null" (4) Either T[] or DOMString could match null, so types of the arguments are not distinguishable and hence the above is invalid WebIDL (5) Neither T[] nor DOMString is inherently Nullable, so a TypeError is thrown Anyone? (Cameron?)
