Stream: Beginner Questions

Topic: Introduced fixed type variable(s)???


view this post on Zulip Yoav Cohen (Jul 22 2026 at 10:38):

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What even is the difference between those instances such that I need to like

fix a :: 'b

in the second one or whatever.

view this post on Zulip Mathias Fleury (Jul 22 2026 at 18:16):

the types to infer are "deferred" to the next line

view this post on Zulip Mathias Fleury (Jul 22 2026 at 18:17):

in a = a, you have no restriction, so you end up with type 'b, while in the first case F a restricts a to be exactly the right type

view this post on Zulip Yoav Cohen (Jul 22 2026 at 18:33):

I don't understand. what kinda restriction does F a put on a's type?

view this post on Zulip Mathias Fleury (Jul 23 2026 at 19:58):

F has a type due to the lemma

view this post on Zulip Mathias Fleury (Jul 23 2026 at 19:59):

the type is inferred there


Last updated: Aug 11 2026 at 20:46 UTC