malcolmsparks

;; Accept-Charset = *( "," OWS ) ( ( charset / "*" ) [ weight ] ) *( OWS
;;  "," [ OWS ( ( charset / "*" ) [ weight ] ) ] )
(let [parser
      (let [charset-with-weight
            (p/sequence-group
             (p/alternatives
              (p/pattern-parser
               (re-pattern charset))
              (p/pattern-parser
               (re-pattern (re/re-str \*))))

kachayev

Aleph, Async, HTTP, Clojure

I've been working with Aleph rougly for last 5 years, actively contributing to the library for last 2 (or so). I also put some effort into spreading the word about it, including educational tech talks, like "Deep HTTP Dive Throught Aleph & Netty". But the more I talk to people the more confusion I find, mostly about how Aleph works and what can you expect when adding it to your stack. Clojurists Together has recently announced Aleph to get Q1 funding, I think it's a good time to share my priorities and thoughts on development plans that were mentioned in the blog post. Hope the community would find it interesting and helpful.

Aleph describes itself as "asynchronous communication for Clojure" library. And you should probably pay a good portion of your attention to the first word: "asynchronous".

pesterhazy

The zprint auto-formatter for Clojure comes with built-in defaults, but it is also highly customizable. The docs can be a bit daunting, so in what follows I will explain how to set some configuration options that are commonly used.

defn

By default, zprint will move the arg vector of defn forms to a separate line:

mfikes

This is a demo of experimental work into ClojureScript parameter type inference.

The work is in a branch, and if you'd like to try out any of this yourself, you can start up a REPL based on the experimental branch using the following command, and play along at home:

clj -Srepro -Sdeps '{:deps {github-mfikes/gist-1e2341b48b882587500547f6ba19279d {:git/url "https://gist.github.com/mfikes/1e2341b48b882587500547f6ba19279d" :sha "55d6c6e9a1c4fc9b58fec74aef1af4aba57bad2a"}}}' -m cljs.main -co @compile-opts.edn -re node -r

To date, all ClojureScript inference "flows" in a certain direction, essentially from primitive values or type-hinted locals to their use sites. For example, consider this expression:

mfikes

If you are curious about the types inferred by ClojureScript, it is easy to get some insight using a macro:

(defmacro inferred-type [form]
  `'~(cljs.analyzer/infer-tag &env
       (cljs.analyzer/no-warn (cljs.analyzer/analyze &env form))))

This is the kind of dev-time macro you could refer using the new user.cljs feature.

bhb

Friendly

A beginner-friendly REPL that combines

• rebel-readline
• Expound
• Speculative

Usage

djspiewak

Quick Tips for Fast Code on the JVM

I was talking to a coworker recently about general techniques that almost always form the core of any effort to write very fast, down-to-the-metal hot path code on the JVM, and they pointed out that there really isn't a particularly good place to go for this information. It occurred to me that, really, I had more or less picked up all of it by word of mouth and experience, and there just aren't any good reference sources on the topic. So… here's my word of mouth.

This is by no means a comprehensive gist. It's also important to understand that the techniques that I outline in here are not 100% absolute either. Performance on the JVM is an incredibly complicated subject, and while there are rules that almost always hold true, the "almost" remains very salient. Also, for many or even most applications, there will be other techniques that I'm not mentioning which will have a greater impact. JMH, Java Flight Recorder, and a good profiler are your very best friend! Mea

favila

(require '[datomic.api :as d])

(d/create-database "datomic:mem://counter-example")
;=> true
(def c (d/connect "datomic:mem://counter-example"))
;=> #'user/c

;; The essential features of creating and using an auto-increment counter in datomic:
;;
;; 1. A counter entity must store the current value and a nonce.

tanaikech

Downloading Shared Files on Google Drive Using Curl

When the shared files on Google Drive is downloaded, it is necessary to change the download method by the file size. The boundary of file size when the method is changed is about 40MB.

File size < 40MB

CURL

filename="### filename ###"
fileid="### file ID ###"
curl -L -o ${filename} "https://drive.google.com/uc?export=download&id=${fileid}"

amalloy

*.clj  diff=clojure
*.cljs diff=clojure
*.cljx diff=clojure