For further consideration...

Tim Keith tim.keith at
Wed Mar 25 09:44:50 PDT 2009

I would like to suggest at least leaving out ?[]

The example in the proposal is not very compelling:
    class Group {
        Person[] members; // null if no members
    class Person {
        String name; // may be null
    final String aMember = g?.members?[0]?.name ?: "nobody";

If members is null you get "nobody" but if members is empty (the logical way
to signify "no members") you get ArrayIndexOutOfBoundsException.

"array?[...]" is like saying: if array is null treat it like it's an
long array of nulls.

"object?.member" is like saying: if object it null, treat it like every
is null and every method returns null.
The array analog to that should be that "array?.length" means
    array == null ? 0 : array.length

-- Tim

On Tue, Mar 24, 2009 at 4:18 PM, Joseph D. Darcy <Joe.Darcy at> wrote:

> Jeremy Manson wrote:
> > Joe,
> >
> > Is it all the Elvis operators, or just ?: ?
> >
> The more modest version is more likely to get in.
> -Joe

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