Evan Patterson (Oct 19 2021 at 05:19): Evan Patterson (Oct 19 2021 at 05:19):A nice feature of map is that it preserves the container type while potentially changing the element type. For example, if you map over a Vector, you get back a Vector, and if you map over a StaticVector, you get back another StaticVector. This is a good reason to prefer map over list comprehensions in some cases.
I'd like the same thing, but for dictionaries. Here's what I'm currently doing. I define a helper function
roottype(T) = T isa UnionAll ? T : T.name.wrapper
and then I write something like
mapvals(f, d::D) where D = (roottype(D))(k => f(v) for (k,v) in d)
This seems to work but it feels bad. Is there a better way?
Kwaku Oskin (Oct 19 2021 at 08:31):Have you seen Dictionaries.jl?
Evan Patterson (Oct 19 2021 at 16:29):It looks very nice, but it's a replacement for the standard dictionary types, right? I was looking for something that would work with Dict, OrderedDict, and other AbstractDict types.
Mason Protter (Oct 19 2021 at 16:35):This would be a nice thing to have. I can’t really think of away to do it other than what you’ve suggested though unfortunately.
Expanding Man (Oct 19 2021 at 16:36):I find the situation with Dictionaries.jl rather frustrating. I agree it is better than Base dictionaries, but so much is already designed to use Base dictionaries that I am hesitant to use it.
Evan Patterson (Oct 19 2021 at 16:39):That is my feeling as well.
Last updated: Nov 27 2025 at 04:44 UTC