does clojure have something like a common lisp (break) statement, or a JS debugger; statement that will allow me to drop into the debugger at a certain point in the code? I am developing in CIDER in emacs and so far I have only been debugging top level forms (`C-u C-M-x`) but I'd like to add a break inside a conditional embedded in a loop that I can stop at instead of stepping my way there.

You can set a breakpoint with a #break reader macro when using CIDER

and then re-evaluate the form

thanks !

I am wondering how Compojure passes contents of a text box back to Luminus. I wrote an HTML form with input boxes like this: <input type="text" name="whatever"> After user clicks Submit, how will user input arrive in Clojure? I assume in some map, but Luminus has a lot of those. Is there anywhere I should look first?

caveat, this is to the best of my knowledge: luminus uses an http server (i don’t know which one) that conforms to the https://github.com/ring-clojure/ring , meaning that it listens to a given port for a “request”, aka data from the internet, and then converts that request into a hashmap of a specific shape that other libraries understand and work with. Then it passes that map to compojure, which understands the ring abstraction too, and reads the keys/values in the request map to determine which route function to pass the request map to

specifically a form submit will be an http request that is a specific shape with a body that is form data https://developer.mozilla.org/en-US/docs/Learn/Forms/Sending_and_retrieving_form_data

good point, thank you

Is there currently beginner-friendly emacs Clojure setup with these properties? 1) cross-platform Mac/Windows, 2) trivial setup/config on both platforms, 3) bracket matching and re-indentation that works on incomplete expressions, 4) all basic functionality (incl buffer management, editing, repl interaction) accessible via menus or other standard UI elements, without requiring understanding emacs-specific concepts or key chords, etc.

I have data like this [5 "missing" "missing" 7] and I want to get answer something like [5 5 5 7] i.e. get the previous element of a vector until I get non missing data, how can I access the previous element in a vector through iteration ?

Specifically iteration? Otherwise this is fairly recursive

I am having a hard time understanding recursion in clojure, so I am not understanding how to achieve it using recursion

Give me a moment to type this out, on phone

clj꞉user꞉> 
(def data  [5 "missing" "missing" 7])
#'user/data
clj꞉user꞉> 
(reduce (fn [{:keys [previous acc]} value]
          (if (= "missing" value)
            {:previous previous
             :acc      (conj acc previous)}
            {:previous value
             :acc      (conj acc value)}))
        {:previous nil
         :acc      []}
        data)
{:previous 7, :acc [5 5 5 7]}

Or that

i’ll type out the equivalent with loop/recur

(loop [acc      []
       previous nil
       data     data]
  (if (empty? data)
    acc
    (if (= (first data) "missing")
      (recur (conj acc previous)
             previous
             (rest data))
      (recur (conj acc (first data))
             (first data)
             (rest data)))))
[5 5 5 7]

Thanks a lot brothers

@mhamzachippa basically what @emccue did but simplified since it's easy to find the last value without needing a composite accumulator

user=> (reduce (fn [acc v]
                 (conj acc (if (= v "missing")
                             (peek acc)
                             v)))
               []
               [5 "missing" "missing" 7])
[5 5 5 7]