Clojurians Log v2

How can I query a data structure like so:

{:a 1
 :b {:a 2}}

(select
    [(specter/recursive-path [] p
                             (specter/cond-path
                               coll? [specter/VAL [specter/ALL p]]
                               :else specter/STAY)))
     ]
)

It might not finish because it was trying to print such a massive value, actually. My bad 🙂 I can't seem to filter the results like I want to though.

so, when you say that you want all :a maps, do you mean you want to traverse the entire tree and get all the values for any :a keys in any nested substructure or you only want to descend the :a branches to look for sub values?

err, what is the intended output with input {:a 1 :b {:a 2}}

are :a values always terminal? can you have {:a {:a 5}}?

@dominicm

(spr/select [(spr/stay-then-continue spr/MAP-VALS) (spr/must :a)] {:a 1 :b {:a 2}})
=> [1 2]

@idiomancy I'm interested in the map itself, rather than the values. I want to traverse the entire tree and get all the values with an :a key.

is my solution giving you the correct answer?

I crave validation

@idiomancy for my particular data structure, just running the stay-then-continue gives me:

clojure.lang.PersistentHashMap cannot be cast to java.util.Map$Entry     

in the actual operation are you doing, like (map #(select [...] %) yourData) ?

Nope, but my data is a list

is it a list of maps or a list of lists?

Oh, I realize I've probably neglected something important. While it is a list of maps, those maps might look like:

{:a 1
 :b [{:a 2}]}

hahaha oh-ho!

well then

yes, mapvals will blow up there

@dominicm

(def dominicm-selector
    (spr/recursive-path [desired-key] p
                        (spr/cond-path
                          sequential? [spr/ALL p]
                          map? [(spr/stay-then-continue [spr/MAP-VALS p])
                                (spr/must desired-key)]
                          :else spr/STAY)))

(spr/select (dominicm-selector :a) [{:a 1 :b [{:a {:a 4}}]}])
=> [1 4]

@idiomancy that's returning a much smaller list than I expected :thinking_face:

I also realize that else branch is unnecessary, I assume all lists only contain maps right? because I realize that selector will also catch any values in lists that aren't maps

Nope 😄 lists can contain anything

this is a massive data structure, and I'm trying to pull out just the bits that I'm interested in.

hahah hmm