XEts.prev

You're seeing just the function prev, go back to XEts module for more information.
Link to this function

prev(tab, key1)

Specs

prev(t() | tab(), any()) :: term() | :"$end_of_table"

Returns the previous item in the table.

Equivalent to :ets.next/2

However, the order in which results are returned might not be the same as the original ETS function, since it's a sharded table.

See also: :ets.pray/2.