Clojurians Log v2

I'm looking for a sample repo to setup a pretty straightforward static file web server using Graal as a learning exercise I found this, which seems good, but is httpkit still the way to go for a http server? I saw the project says it's unmaintained by the owner but maintained by community users. https://github.com/yogthos/graal-web-app-example

what a great idea! 🙂

I don't know any other IDE besides emacs... as in emacs i paste in stdin : PasteTheAuthCodeHere . you should ask others who use vscode where to paste the authcode

Since updating the byte-array is faster, I started to focus on how to get the results from it faster. The reducers solution was one such attempt. Also tried core.async/pipeline, but that was super slow, some 200X slower. It’s not a big enough problem for that tool. 😃 But then I got a tips to try with loop and that does make a difference. Not huge, but anyway:

(defn pez-ba-loop-sieve [^long n]
  (let [primes (boolean-array (inc n) true)
        sqrt-n (int (Math/ceil (Math/sqrt n)))]
    (if (< n 2)
      '()
      (loop [p 3]
        (if (< sqrt-n p)
          (loop [res []
                 i 3]
            (if (<= i n)
              (recur (if (aget primes i)
                       (conj res i)
                       res)
                     (+ i 2))
              (concat [2] res)))
          (do
            (when (aget primes p)
              (loop [i (* p p)]
                (when (<= i n)
                  (aset primes i false)
                  (recur (+ i p p)))))
            (recur  (+ p 2))))))))

Finally got it guys, it needs to be run in repl

@cjpangilinan - I’ll check that one out. Thanks for the tip! I’d not seen that one before.

Hi there, folks. I’ve been working on Code Academy “katas” like a good beginner, and I came across this bit of irritation: https://www.codewars.com/kata/5ce399e0047a45001c853c2b/train/clojure > Let us consider this example (array written in general format): > ls = [0, 1, 3, 6, 10] > Its following parts: > ls = [0, 1, 3, 6, 10] > ls = [1, 3, 6, 10] > ls = [3, 6, 10] > ls = [6, 10] > ls = [10] > ls = [] > The corresponding sums are (put together in a list): `[20, 20, 19, 16, 10, 0]` So, I whipped up the following bit of code, which I was rather proud of!

(defn parts-sums [ls]
  (if (empty? ls) '(0)
      (cons (reduce + ls) (parts-sums (rest ls)))))

What if you reverse the list first?

Trying to just give vague hints here so as not to give away spoilers. 🙂

thanks. I will look into it. 🙂

I'd also look at the function reductions

Or another question: what’s the most time-consuming part of the problem, and how can you minimize the time you spend doing that?

That’s a better approach to figuring out optimizations in general.

e.g.

(reductions + 0 [1 2 3 4 5])
=> (0 1 3 6 10 15)

Hmmm… I’d never seen or tried to use the function reductions before. One of my attempts was trying to use reduce but that didn’t work.

It's like reduce, but returns you the intermediate values

Note that the correct solution to the problem given is The corresponding sums are (put together in a list): [20, 20, 19, 16, 10, 0]

YESSSSS, reductions! I just looked up that up. That’s exactly what I need here!

I’d never heard of it before!

Clojure has a bunch of useful things like that. See also frequencies, which isn’t relevant to this, but it’s also a cool function.

[heads off and fires up emacs]

Team, I have service endpoint which has authentication, I am able to get the result in postman, I wanted to integrate same in my application using clojure, Which are the api I can use? I started with composure, But I did not get how to access endpoint via clojure

As a client, there are several, for example <https://http-kit.github.io/> and <https://github.com/dakrone/clj-http> are two that immediately come to mind.

So we need to use ring in this?

No. If I read you correctly, you want to invoke an external 3rd party API that is secured by some type of authentication, in order to retrieve data (most likely JSON)?

Execution error (SunCertPathBuilderException) at sun.security.provider.certpath.SunCertPathBuilder/build (SunCertPathBuilder.java:141). unable to find valid certification path to requested target

@dharrigan ^^

So in order to set a custom read timeout in a google analytics api request, I had to write https://developers.google.com/api-client-library/java/google-api-java-client/errors in clojure with java interop. I ended up using reify:

(defn set-http-timeout [request-initializer]
  (reify HttpRequestInitializer
    (initialize [_ http-request]
      (.initialize request-initializer http-request)
      (.setReadTimeout http-request (* 3 60000)))))

That's an interface not a class

(Yup, it's official, I'm an idiot 😅) Thanks!

Hi, can I ask for some support? I have a Leiningen project that does not work for some reason but I don't know why. https://github.com/audriu/gorilla-rpl-try I run lein gorilla` as shown in this example http://gorilla-repl.org/start.html I just need to find out if this is problem with my setup or I am doing something stupid. The exception is here: https://pastebin.com/9B2QDtrr

The project was created with lein new app name and just added :plugins [[lein-gorilla "0.4.0"]] to project.clj

When I publish a Clojure library to Clojars, I see allow just for “org.clojars.baader/*” to submit something, but how could I create eg [baader/library-name “0.1.0"], without org.clojars? Just I don’t understand others.. how could setup this.

Clojars policies have changed over time

There were some recent changes to prevent people from using group I'd names that they don't "own" in some sense

https://groups.google.com/g/clojure/c/cWG-V_4uv90

https://github.com/JonyEpsilon/gorilla-repl/issues/291ou are hitting this issue.

https://github.com/JonyEpsilon/gorilla-repl/issues/291

change reps in plugins section as mentioned in the comment to [org.clojars.benfb/lein-gorilla "0.6.0"]

thank you so mutch

@sb Both clj-new and depstar will be getting updates this week to "strongly encourage" folks to use group IDs that comply with the new security policy that Clojars is rolling out.

If you own <http://baader.com|baader.com> (or .net or .org) you should probably use com.baader as your group name (or net.baader or org.baader) so that ownership can be verified. Or com.github.baader if your library lives on GitHub.

I use Hungarian domain (my company domain), in this case hu.baader ok, btw during this time somebody approved to use baader name (thanks!)

hu.baader/library-name would be nice for you to use (and make sure you don't conflict with any other baader out there 🙂 )

ok 🙂 I can do it. Np for me 🙂

works fine, thanks!!

Enter transient. 😃

(defn pez-ba-loop-transient-sieve [^long n]
  (let [primes (boolean-array (inc n) true)
        sqrt-n (int (Math/ceil (Math/sqrt n)))]
    (if (< n 2)
      '()
      (loop [p 3]
        (if (< sqrt-n p)
          (loop [res (transient [])
                 i 3]
            (if (<= i n)
              (recur (if (aget primes i)
                       (conj! res i)
                       res)
                     (+ i 2))
              (concat [2] (persistent! res))))
          (do
            (when (aget primes p)
              (loop [i (* p p)]
                (when (<= i n)
                  (aset primes i false)
                  (recur (+ i p p)))))
            (recur  (+ p 2))))))))

Evaluation count : 60 in 6 samples of 10 calls.
             Execution time mean : 10,599681 ms
    Execution time std-deviation : 163,784470 µs
   Execution time lower quantile : 10,417649 ms ( 2,5%)
   Execution time upper quantile : 10,831060 ms (97,5%)
                   Overhead used : 14,507923 ns

(defn pez-ba-sieve [^long n]
  (let [primes (boolean-array (inc n) true)
        sqrt-n (int (Math/ceil (Math/sqrt n)))]
    (if (< n 2)
      '()
      (loop [p 3]
        (if (< sqrt-n p)
          (concat '(2)
                  (filter #(aget primes %)
                          (range 3 (inc n) 2)))
          (do
            (when (aget primes p)
              (loop [i (* p p)]
                (when (<= i n)
                  (aset primes i false)
                  (recur (+ i p p)))))
            (recur  (+ p 2))))))))

Evaluation count : 24 in 6 samples of 4 calls.
             Execution time mean : 25,913184 ms
    Execution time std-deviation : 569,484180 µs
   Execution time lower quantile : 25,135620 ms ( 2,5%)
   Execution time upper quantile : 26,538920 ms (97,5%)
                   Overhead used : 14,507923 ns

What kind of authentication are you using?

My guess from the error is that you are using a self-signed certificate?

@popeyepwr If you are using clj-http, you should look at the :insecure? or :keystore options. http-kit has the :insecure? option but I'm not sure how it handles :keystore

Good afternoon everybody, I'm back at it with more livestreaming today. We're starting in about 10 minutes if you'd like to join. Stream link here: https://www.twitch.tv/a_fry_ Per usual, I'm mostly going to be live-coding the development of this app: https://startupinamonth.net/pic-story-pitch/ But first I'm starting with a coding exercise warmup, so if you're new to the language, are trying to learn new techniques, or just curious, then feel free to join for the exercise portion! We're doing this coding challenge from the Eric Normand newsletter today, averaging RGB colors: https://purelyfunctional.tv/issues/purelyfunctional-tv-newsletter-400-is-software-design-worthless/ Hope to see you there :man-bowing:

is there a way to change the ring anti forgery token error page?

https://github.com/ring-clojure/ring-anti-forgery/blob/master/src/ring/middleware/anti_forgery.clj#L69-L73

Watching REPL Driven Development on http://clojure.tv to learn different programming flow with Clojure. Any other suggestions? I’m currently using Cursive since I’m most comfortable there. Any good resources for RDD in Cursive would be awesome!

@twcrone I don't know of any that use Cursive (maybe ask in #cursive?). I have a couple of videos on my YouTube channel that show my RDD workflow (with Atom/Chlorine and Cognitect's REBL) https://www.youtube.com/c/SeanCorfield_A and I did a couple of meetup talks/live coding recently with VS Code/Clover and Reveal https://www.youtube.com/watch?v=gIoadGfm5T8 (London: an hour and fifteen) and https://www.youtube.com/watch?v=skEXGSp10Xs&t=837s (Provo: the talk starts 14 minutes in and runs 2 1/2 hours).

I love Eric Normand's RDD course on http://PurelyFunctional.tv but that's a subscription service ($49/month).

There's also this from Practicalli: https://practicalli.github.io/clojure/repl-driven-devlopment.html

can’t subscribe anymore…need to pay per video although they are downloadable for free it appears

yes, saw that too

I've pinged Eric about the subscription stuff -- he still links to it in his weekly newsletter, saying subscriptions are available. I know he closed them down for a while, then opened them back up.

ok, I seem to remember seeing subscriptions were available recently, then last couple days could not get one.

If anybody would like to check out my solution, here it is: https://github.com/andyfry01/clojure-coding-challenges/blob/master/src/main/color-averaging.clj You should be able to copy/paste this into any old REPL and just run it. Enjoy!