Can @view be used along with dataframesmeta

New to Julia
,
1

I am trying to update values of a column in a dataframe and I see that I can use @view macro to reference the dataframe. Is there a way to use @view from dataframes and @subset from dataframesmeta to update a column value.

using DataFrames, DataFramesMeta
test = DataFrame(x = [1,2,3,4], y = [5,6,7,8])
@view test[2:3, :]

Suppose I want to update 2nd and 3rd row values of x column, how would I do it using dataframesmeta but at the same time take advantage of referencing the original dataframe (like @view does).

2

No. That is not yet possible.

DataFrames.subset provides a view = true keyword argument. But DataFramesMeta.jl macros do not yet support keyword arguments.

DataFrames.jl only very recently added transform! to do what you want an act on views. We have not yet added a fully-featured API DataFramesMeta.jl. In the meantime you could get on the latest version of DataFrames.jl and do something like

@chain df begin 
    view(2:3, :)
    @transform! :y = f(:x)
end

and see if that works.