recently I am interested in writing script with Clojure, I don't know if there is any example, can someone help me out?

@steiner3044 You'll need to be a bit more specific -- what sort of script do you want to write? What are you already familiar with?

How familiar are you with Clojure so far? What tutorials have you already read? This one? https://clojure.org/guides/getting_started

How would I catch an exception thrown in a lazy sequence and continue? I'm using org.clojure/data.csv and a CSV error is being thrown for one of the rows but, at least for now, I want to just skip those rows and continue

@kyle That's going to depend on exactly what's causing the exception and where.

If the exception is coming from inside that library and it's failing to produce more elements of the sequence, you won't be able to fix that without patching the library. If the exception is coming from your own code, you probably could make it more robust.

Its coming from inside the library. I am transforming the lazy seq produced by org.clojure/data.csv with map . I don't know how I would continue without translating it to a (loop) and getting the first element of the lazy sequence inside a try-catch

Well, you could map "bad" rows to nil and then filter those out -- if data.csv continues to produce elements beyond the row you cannot consume.

(filter some? (map (fn [row] (try (your-normal-process row) (catch Exception _))) data-csv-rows))

(assuming your-normal-process itself is eager)

Does that work if (first csv-lazy-seq) would throw if the first CSV row in the file is invalid? It is throwing a plain java Exception

Right, that goes back to my question about exactly where the exception is originating.

This is the source of the throw if you're curious https://github.com/clojure/data.csv/blob/data.csv-1.0.0/src/main/clojure/clojure/data/csv.clj#L37

Yeah, if the CSV file is unparseable, there's very little you can do: the library simply cannot recover from the error.

I am new to protocols and mixins. In The Joy of Clojure, the authors write that mixins and protocol extensions are fully open. What does fully open mean here?

I am guessing it means they can be extended at any time and place (before usage).

It means that new extensions can be added at any time, without modifying the original definition

Hey friends, I'm trying to do a basic query in datomic and the docs aren't quite clicking for me. I have this test dataset:

(def first-movies [{:movie/title "The Goonies"
                      :movie/genre "action/adventure"
                      :movie/release-year 1985}
                     {:movie/title "Commando"
                      :movie/genre "thriller/action"
                      :movie/release-year 1985}
                     {:movie/title "Repo Man"
                      :movie/genre "punk dystopia"
                      :movie/release-year 1984}])

(d/q '[:find ?title
         :where ;[]
         [?title :movie/title ?title] ] db)

Curious if anyone has experience turning clojure spec into json schema --- if it's viable/worth the effort?

I've done it

I did it to describe an api to our front end guys, but in the end it wasn't enough, you can describe data types with it, but you can't describe an operation (do this, then you get this result) and that was more of what I needed

but it is neat, and atleast for the trivial things, trivial, because you can get the un-eval'ed form of a spec out of a spec, you just write an interpreter for those

yeah, i was wondering how complete of a json spec you can create. I would only be describing data (preferably to the level of "if you pass this, then this other thing is required"). Actually i didn't know you could specify operations in json schema, or missing what you mean there... sounds like swagger-like (which i don't need)

one impl of spec -> json schema in spec-tools: https://cljdoc.org/d/metosin/spec-tools/0.10.4/doc/json-schemas

cool. i think i need to see if/how to compose specs. For example, have a basic spec, where little/nothing is required, but be able to layer on specific/more stringent cases.

yeah, swagger like (but of course swagger didn't work because it isn't a rest api, and there are async parts, etc)

Hi all ! Quick question. I’m using reitit router on the frontend and the backend. How can I forward urls to the frontend router? I have routes which work like /#/great/person . However, when I navigate to that route using the browser, I’m redirected to #/ instead of the route.