Request for clarification - 8.17.5. Range Input/Output

The following documentation comment has been logged on the website:

Page: https://www.postgresql.org/docs/9.6/static/rangetypes.html
Description:

Hi,

I am reading this section of the manual and the results I see are not what I
expect according to the examples, except for the last example showing empty.

Perhaps I have misunderstood the comments, but take the first example:

-- includes 3, does not include 7, and does include all points in between.

I expect the results of the select, from my reading, to show 3,6. However
when I try this I see 3,7:

jredb=> SELECT '[3,7)'::int4range;
+-----------+
| int4range |
+-----------+
| [3,7) |
+-----------+
(1 row)

Similarly the next two examples show different results to my expectations: I
see 4,7 and 4,5.

Can somebody explain if my understanding is wrong, and kindly post the
results they see?

Thanks,
J.