Best practices for type dispatch?

[ChrisRackauckas]

Duplicate. Here’s my answer.

Singleton types vs. instances as type parameters

Oh yes, this question . Fond memories. In JuliaDiffEq, we had a similar problem: what should solve(prob,alg) dispatch on, the type of alg or its instance? We had a month where we: Went with the type Went to the instance Went back to the type Finally at the instance. It has stayed with the instance ever sense. Example: solve(prob,RK4()) The reason is because this is much more flexible. It took me awhile to get here though! Arguments are given here: https://github.com/Julia…