[ruby-core:72818] Re: [Ruby trunk - Bug #11975] Range#last is not consistent and possibly does not do what is expected.

I haven't found this behaviour surprising at all. Maybe it=92s because I'm =

almost always using literal ranges and this lead me to think of =

`Range#last` as =93give me the last element of the range=92s _definition_ =

(regardless of exclude_end?)=94, i.e. I expect `(0...1).last` to behave =

like `[0, 1].last`.


Am 12.01.16 um 10:08 schrieb [e-mail]:
> Issue #11975 has been updated by Samuel Williams.
>
>
> Nakada-san, `(0.0...1.0).last` would probably give the same error as `(0.=
0...1.0).to_a`?
>
> Marc, even though it's intentional, and even documented, it's still not o=
bvious that this is desirable behaviour. What I did find, is an equivalent =
method, `max`, which does do what I needed. I know practically speaking tha=
t this is not possible to fix this issue. Perhaps the best course of action=
 would be to (a) not do anything or (b) deprecate `last` since it's behavio=
ur is confusing and there are several alternatives.
>
> ----------------------------------------
> Bug #11975: Range#last is not consistent and possibly does not do what is=
 expected.
> https://bugs.ruby-lang.org/issues/11975#change-56059
>
> * Author: Samuel Williams
> * Status: Rejected
> * Priority: Normal
> * Assignee:
> * ruby -v: 2.3.0
> * Backport: 2.0.0: UNKNOWN, 2.1: UNKNOWN, 2.2: UNKNOWN, 2.3: UNKNOWN
> ----------------------------------------
> The following example demonstrates an inconsistency with Range:
>
> This is expected behaviour:
>
> ~~~
> (0..10).last =3D> 10
> (0..10).to_a.last =3D> 10
> ~~~
>
> This is unexpected behaviour:
>
> ~~~
> (0...10).last =3D> 10 # (should be 9?)
> (0...10).to_a.last =3D> 9
> ~~~
>
> I believe that Range#last should give the last valid value for a range. D=
iscussion?
>
>
>


Unsubscribe: <mailto:[e-mail]?subject=3Dunsubscribe>
<http://lists.ruby-lang.org/cgi-bin/mailman/options/ruby-core>