This doesn't work, at least for me on 1.10. `round(; digits=2)` would have to produce a function. But Julia doesn't have automatic currying, so that only happens if someone has implemented a special-case version (e.g. (==)(3) returns a partial function that tests for equality with 3.)
array |> mean |> round
For scenarios with named arguments there is a little not so cleaner workaround
array |> mean |> x->round(x, digits=2)