This is kind of a noob js/cljs question. I'm adding an event listener to js/document but whenever figwheel hot reloads the page it gets added again. I tried to prevent it by doing this but it keeps on doing the same. (I saw something like this on a Reagent example with js/setInterval so I expected it to work the same).

Hey, I'm new to clojure and clojure.test . So I've written a simple test case for the project while running C-c C-t p or C-c C-c n it is showing "Not a NREPL dict"

Can anyone tell me how to rectify that error(Not a nRepl dict)

Is there a way to auto load my clj file on save into the cider repl on emacs? It's pretty annoying having to C-c C-l or C-c C-kevery time I make a change to the file.

@nicholas.jaunsen personally I’d like to have control over that, but if you’re into this, you can use the reloaded workflow and hook it up to an emacs hook

@nicholas.jaunsen this way of working traces back to this: http://thinkrelevance.com/blog/2013/06/04/clojure-workflow-reloaded

Can some one point me to what I'm doing wrong here:

(defn create-list [num]
  (let [awnser []]
    (if (empty? num)
      awnser
      (recur (int (/ num 10))
             (conj awnser (mod num 10)))))

I get a argument count error on the recur

it looks like you're recurring with two arguments, but create-list only access one argument num

you've got two arguments to recur, but only one in your function

you want (loop [num num answer [] instead of (let [answer [] (p.s. you got a typo)

also you should use loop/recur

basically what they said

@restenb why 2 times num?

you can also use multiarity to "kick start" the recursion if no answers are yet known:

(defn create-list
  ([n]
    (create-list n []))
  ([n answers]
    (if (< n 10)
      (create-list (inc n) (conj answers n))
      answers)))

(create-list 0)
=> [0 1 2 3 4 5 6 7 8 9]

note that recur doesn't play nice with multiarity. it will try to recur on the same function and you'll get the same argument mismatch error

(loop [num num answer [] just binds your num function parameter to a num local var inside the loop

ah

restenb's answer is cleaner 🙂 just showing you a more verbose recur

it would help to know what you're trying to do, there's a couple other problems in the function you posted

like it'll probably end up being an infinite recursion if you pass it a number

I'm trying to turn a number into a list of seperate digets. But empty? on a number cant work 🙂

got it working

(defn create-list [num]
  (loop [num num awnser []]
    (if (= num 0)
      awnser
      (recur (int (/ num 10))
             (conj awnser (mod num 10))))))

yes, that might work. the problem I saw was with the (if (empty? num) as I that would seemingly always return false on a number

now your recursion is well-formed with a termination condition on num = 0

also if you're trying to split a number into a list of digits, that can probably be done more readily by just converting the number to string first

(->> num str (map (comp read-string str)))

that will take num as a number and return a list of it's digits, as numbers, by way of string

yes, I was thinking about using a string first, but I wanted to try and use a solution with modulus.

threading macro is also something I need to spend some more time with

I'd still prefer to do this without recursion though

or, without loop/recur I should say

that's a suggested solution using mod and quot

@shidima a bit hacky maybe: (defn digits [n] (map #(- (int %) 48) (str n)))

now do a negative number!

you can also just do (map #(Character/digit % 10) (str num))

@restenb but your digits is still using recursion right?

and that'll ... sort of work on negative numbers (first digit becomes -1 if number is negative)

1. @shidima yes, just highlighting that setting up an explicit loop/recur isn't necessary to solve the problem

the above example with quot and mod is the most efficient by far though since you avoid conversions. it can be extended to tackle negative numbers fairly easily

Well, with some help I did the armstrong-numbers problem from http://exercism.io 🙂 Thanks all!

any pointers on why (mapv #(mapv % (keys (@db :input))) (@db :input)) fails with error: IllegalArgumentException Key must be integer clojure.lang.APersistentVector.invoke (APersistentVector.java:294) :start-time and :end-time contain java.time.Instant and :duration is an integer

Is columns meant to be a nested sequence like that?

I'm not sure, I'm just trying to save a csv with headers, using the keys in the map as the header names. then later I have another function which just appends to this csv without creating the headers

Hello I tried to use coast. I had few issues with it.

[email protected]:~/projects/rubbish$ coast new myapp && cd myapp
/home/foobar/bin/coast: 7: /home/foobar/bin/coast: [[: not found
/home/foobar/bin/coast: 17: /home/foobar/bin/coast: [[: not found
/home/foobar/bin/coast: 7: /home/foobar/bin/coast: [[: not found
/home/foobar/bin/coast: 27: /home/foobar/bin/coast: [[: not found
Downloading a fresh copy of coast...
Created a new coast project in directory myapp

[email protected]:~/projects/rubbish/todos$ make db/create
clj -A\:db/create
Exception in thread "main" java.io.FileNotFoundException: -A:db/create (No such file or directory)

.PHONY: test

test:
	COAST_ENV=test clj -A\:test

clean:
	rm -rf target

uberjar:
	clj -A\:uberjar

repl:
	clj -R:repl bin/repl.clj

db/migrate:
	clj -A\:db/migrate

db/rollback:
	clj -A\:db/rollback

db/create:
	clj -A\:db/create

db/drop:
	clj -A\:db/drop

jobs:
	clj -m 

assets:
	clj -m coast.assets

routes:
	clj -m coast.router

I'm afraid that coast is not mature enough... I'm Thinking about returning to Compojure

One more question, is there Clojujre alternative to activeadmin? https://activeadmin.info/

what is coast?

https://github.com/coast-framework/coast

@seancorfield I think I understand now, the issue is here (let [columns [(keys data)], so I have a list inside a vector. How do I get rid of that?

Has anyone set up in emacs a way for the kill command to skip putting a killed selection on the kill ring if the selection is just an empty string/blank lines?