WordPress Codex has different number of arguments for get_previous_post and get_next_post functions. Why?

Compare the following two links:

https://codex.wordpress.org/Function_Reference/get_next_post https://codex.wordpress.org/Function_Reference/get_previous_post

The get_previous_post function doesn’t have the last $ taxonomy parameter, while get_next_post has it listed. I followed those instruction literally, which caused my get_previous_post to break. When I noticed the difference between the two functions, I tried specifying the taxonomy in my get_previous_post function, which fixed the problem. Is this a mistake in the Codex for get_previous_post?