is AFTER-ELEM used in selections or is just primarily used with setval ? I want to make sure my koans cover possible use cases unless it doesn't make sense.

also, I watched the talk and was excited about specter keeping the collection type the same so I was surprised when I saw this (setval AFTER-ELEM 2 #{1 2}) => (1 2 2)

the set was turned into a list

it does the same thing for a map

I tried to pass a k/v pair to AFTER-ELEM as two args and go a wrong number of args error

when I put the k/v pair as a map it just turned the original map into a vector, added it to a list and then added my k/v argument as a separate map in the list like this: (setval AFTER-ELEM {:friend "Mary"} {:name "Paul"}) => ([:name "Paul"] {:friend "Mary"}) so since the result isn't treated like a map you don't need k/v pair balance (setval AFTER-ELEM "Mary" {:name "Paul"}) => ([:name "Paul"] "Mary")

I just want to make sure I'm not documenting nonsense cases

@gdeer81 AFTER-ELEM is only intended for transformations

it doesn't make sense in the context of a set

to add a single element to a set most efficiently use NONE-ELEM

likewise, it doesn't make sense in the context of a map

for a map, just use keypath

I figured that was the case

so for each navigation I'm trying to document intended use and collection types

cool, that's good

would be a good thing to add to the docstrings too

ha or even the spec, "spec error: you shouldn't be using this on a set"

Does Specter have specs? I didn't think it did

I'm pretty new to specs but I'd be willing to help spec Specter if that's of interest

Yeah, took another look and pretty sure it doesn't, since it's on 1.8.0 and there's no files included

@nathanmarz (let [my-vec ^{:author "Gary"} [1 2 3]] (meta (select ALL-WITH-META my-vec))) returns nil , am I doing something wrong or is this a bug?

@gdeer81 @nathanmarz I took a look, it looks like meta is preserved with a transform but not with the select implementation, you can see it in the code too

(let [my-num ^{:author "Gary"} [1]] (meta (transform ALL-WITH-META inc my-num)))

(defnav ^{:doc "Same as ALL, except maintains metadata on the structure."} ALL-WITH-META [] (select* [this structure next-fn] (n/all-select structure next-fn)) (transform* [this structure next-fn] (let [m (meta structure) res (n/all-transform structure next-fn)] (if (some? res) (with-meta res m) ))))

I think I can file a patch 🙂

there's no metadata to maintain on select, since it navigates into the subvalues

that nav purely exists for transforms, especially for codewalker

@nathanmarz Ah, looks like this one isn't in the docs either, I'll submit a pr for it

I'm going to stick to creating koans for the things documented in the wiki until I'm more attuned with the code

Sent in a PR, and a few related to a new issue I opened about undocumented vars: https://github.com/nathanmarz/specter-wiki/issues/17

Hi everyone, I made a screencast to introduce Specter to newcomers: https://www.youtube.com/watch?v=rh5J4vacG98