Zulip Chat Archive

Stream: mathlib4

Topic: associativity of `∘L`


Jireh Loreaux (Jul 10 2025 at 17:47):

The infix notation ∘L for continuous linear maps is declared to be right associative, which conflicts with the fact that * is declared left associative.

Consequently, f₁ ∘L f₂ ∘L f₃ = f₁ * f₂ * f₃ is not defeq, which is super annoying. Is there a reason we've caused ourselves this headache?

Aaron Liu (Jul 10 2025 at 17:50):

That looks like it should be defeq

Jireh Loreaux (Jul 10 2025 at 17:52):

Oh nevermind, I'm an idiot

Jireh Loreaux (Jul 10 2025 at 17:55):

I was having a different problem and misdiagnosed.

Aaron Liu (Jul 10 2025 at 19:08):

I imagine the reason is because comp is also declared to be right associative.


Last updated: Dec 20 2025 at 21:32 UTC