access an element with empty name

Serguei Sokol writes:

Hi,
I came across a case where I cannot access a list element by its empty name.
Minimal example can be constructed as
  ??? x=list("A", 1)
  ??? names(x)=c("a", "")
  ??? x[["a"]]
  ??? #[1]? "A"
  ??? x[[""]]
  ??? #NULL
  ??? x$`a`
  ??? #[1]? "A"
  ??? x$``
  ??? # Error: attempt to use zero-length variable name
  ??? # but we can still access the second element by its index
  ??? x[[2]]
  ??? #[1] 1
To my mind, it should be perfectly legal to access an element by an
empty name as we can have for example
  ??? match("", names(x))
  ??? #[1] 2
Hence a traditional question: is it a bug or feature?

A feature according to the docs: ? Extract says

     Neither empty (?""?) nor ?NA? indices match any names, not even
     empty nor missing names.