tar_combine() some but not all branching variables?

[potash]

Another thing I am doing in my static branching pipelines is combining over some but not all of the variables in a tar_map(). E.g. if we mapped over variables a and b we then collapse to branching over a by combining all of the bs for a given value of a. I have some code to do this that I can share but I thought I'd check first whether there's already a way to do this. Thanks!

[wlandau]

I would have a look at tar_select_names() and tar_select_targets(). You can supply the output to tar_combine().