Zulip Chat Archive
Stream: new members
Topic: Linear orders
Heather Macbeth (Jul 29 2020 at 13:56):
I am trying to navigate the order
library. How would I express that something is a linear_order
and also has ⊤
and ⊥
elements? Do I use [linear_order ι] [bounded_lattice ι]
? (I fear that I would be introducing an order twice by doing this.)
Johan Commelin (Jul 29 2020 at 13:59):
Yup... that wouldn't work :sad: It would be nice to have mixins here...
Johan Commelin (Jul 29 2020 at 13:59):
I guess complete_linear_order
gives you more than you want, right?
Heather Macbeth (Jul 29 2020 at 14:01):
It's more than necessary. But it's fine for my purposes (closed intervals in the reals, ultimately). Thanks!
Adam Topaz (Jul 29 2020 at 14:36):
That's strange... Closed intervals form a linear order? Doesn't linear order require that any two things are comparable?
Heather Macbeth (Jul 29 2020 at 14:44):
The order on the points in a single closed interval.
Adam Topaz (Jul 29 2020 at 14:46):
Oh :)
Yury G. Kudryashov (Jul 30 2020 at 03:56):
If you're going to add a def for
complete_linear_order (Icc a b) it should assume
conditionally_complete_linear_order α. It can't be an
instance because it also needs
a ≤ b`.
Last updated: Dec 20 2023 at 11:08 UTC