ceylon/ceylon-js — comment on commit 6c40daa2262dfdf698cdf67963eead4b26798dd1
File:  line 0
By chochos:

But OTOH the spec says `lhs?.member` is equivalent to `if (exists lhs) lhs.member else null` and from this I understand that lhs will always be an object reference; I don't think `f()?.x` is a valid expression (but I have to test that).