Description
I should have added this in #64.
But it makes sense to add combine here to so that DimensionalData.jl can use it and not clash with DataFrames.jl.
One question I have is the argument order. In DD it would make sense to do something like:
combine(mean, groupby(dimarray, Ti=>month); dims=Ti)And allow a do block for the function in combine.
But DataFrames.jl is using a different syntax: combine(df, [:X, :Y] .=> mean) where the functions are in the second argument, and they are connected to columns so a do block cant work anyway.
Maybe the rule can be the extending package must either 1. own the first argument, or 2. own the second argument where the first is <:Function ? With the downside that the owned object cant be <: Function in 1.
The other option is DD uses combine(groupby(dimarray, Ti=>month), mean; dims=Ti), its just unfortunate to break the usual function-first argument order.