How to deal with character(0)

Let x <- character(0)
x == character(0) returns logical(0), which is not what we expect.

A solution is to test:
identical(x, character(0))

But it does not work if x has attributes.

Then, do:
attributes(x) <- NULL
identical(x, character(0))

or 


(length(x) == 0) && (typeof(x) == "character")

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