bug#64960: Documentation for copy-sequence

[uzibalqa]

Have been reading the documentation for "copy-sequence".  The description,
specifically

"The elements of a list, vector or record are not copied; they are
shared with the original."

is not very clear about what it does and what one gets.

--------------------

copy-sequence is a built-in function in ‘C source code’.

(copy-sequence ARG)

Type: (function (sequence) sequence)

Return a copy of a list, vector, string, char-table or record.
The elements of a list, vector or record are not copied; they are
shared with the original.

If the original sequence is empty, this function may return
the same empty object instead of its copy.

This function does not change global state, including the match data.