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One thing I don't like about all articles on clojure is that basically all of them say: ah, it's just like lisp with lists `(an (example of) (a list))` with vec

One thing I don't like about all articles on clojure is that basically all of them say: ah, it's just like lisp with lists `(an (example of) (a list))` with vectors `[1 2 3]` thrown in. So easy! But then you get to Clojure proper, and you run into additional syntax that either convention or functions/macros that look like additional syntax. Ok, granted, -> and ->> are easy to reason about (though they look like additional syntax). But then there's entirely ungooglable ^ that I see in code from time to time. Or the convention (?) that call methods on Java code (?) with a `.-` Or atoms defined with @ and dereferenced with * Or the { :key value } structure There's way more syntax (or things that can be perceived as syntax, especially to beginners) in Clojure than the articles pretend there is. (defn ^:export db_with [db entities] (d/db-with db (entities->clj entities))) (defn entity-db "Returns a db that entity was created from." [^Entity entity] {:pre [(de/entity? entity)]} (.-db entity)) (defn ^:after-load ^:export refresh [] (let [mount (js/document.querySelector ".mount") comp (if (editor.debug/debug?) (editor.debug/ui editor) (do (when (nil? @*post) (reset! *post (-> (.getAttribute mount "data") (edn/read-string)))) (editor *post)))] (rum/mount comp mount)))

cr__ 5y ago
Not sure how you’re supposed to find this page, but it’s pretty useful: https://clojure.org/guides/weird_characters https://clojure.org/guides/weird_characters
- dmitriid 5y ago
  Nice! I missed it (or it didn't exist) when I last looked at Clojure a few years back
  - roenxi 5y ago
    You missed it, it has been there forever. But it says good and bad things about Clojure that its reference documentation is one of its weakest points. The Guide/Reference split obscures a lot of information (do I want guidance on Deps & CLI or do I want reference on Deps & CLI?) and the guides where that gem is hidden randomly mix advanced topics (eg, how to set up generative testing), beginner topics (how to read Clojure code) and library author topics (eg, Reader Conditionals). When you think about it, there is nearly no trigger to look at the guides when the information you need is there. Clojure is a weird mix of both well documented and terribly documented. All the facts are on the website, very few of them are accessible when required. The people who make it past that gauntlet are rewarded by getting to use Clojure.
    - dmitriid 5y ago
      In my case it was even worse, as I started with ClojureScript, and official documentation was simply abysmal then.
ronnier 5y ago
Single engineers will pick clojure at companies , build a project in it, later that engineer will move on, now nobody can maintain this code so it’s rewritten in some normal language. I’ve seen that happen a few times. That code is hard to read and understand. This is why clojure will remain niche.
- taeric 5y ago
  That is possible with all languages. I've seen java, scala, clojure, perl, python, etc. Usually this is made worse by bespoke build tools and optimizations that make the system punishing to pick up.
  - sramsay 5y ago
    You've seen a case where someone wrote something in Python that later devs could not understand and then rewrote it in . . . what? And you've seen that with Java? There's a big difference between a developer going off and writing something in one of the top five most used languages in the world and doing so in Scala.
    - lostcolony 5y ago
      Both are strange and alien to Javascript developers, who can be full stack. Python may seem simple once you know it, but going in blind there's plenty of traps to bite you. Significant whitespace for one.
      - chrsig 5y ago
        I think there's two different issues: 1. picking a language/tool that a company doesn't have personnel with experience using it 2. picking a language/tool that is esoteric, which generally implies #1 as well. #1 on its own isn't great, but generally when sticking in the java/python/ruby/javascript/php/etc...mainstream languages, there's a lot more documentation, and there's a higher chance that _someone_ in the company will have some familiarity. If nothing else, it'd be easier to hire a replacement for.
lvh 5y ago
Minor point of order about the atoms: they're not defined with @ nor derefd with . If you're referring to earmuffs* that's convention not syntax (specifically for dynamically scoped variables, which could be atoms or anything else), and @ is indeed deref. (More specifically @x is a reader macro ish that expands to literally `(deref x)`.)
- dmitriid 5y ago
  Thank you! I never seem to remember this (but I don't use Clojure, so it's not an ingrained knowledge)
girishso 5y ago
Agreed. These days I'm really fascinated by clojure and trying to learn clojure. Other than the project setup and repl and the editor (which I had considered), these weird characters are throwing me off. What clojure really needs is some kind of opinionated framework or starter template, something like create-react-app. That has all these things figured out so a beginner like me can start playing with actual clojure, which documents all the steps to setup the repl and editor and what not. The last time I asked for this I was told about lein templates, they help but there's no documentation to go with those. There needs to be some push from the top level. create-react-app was produced by facebook. Elm reactor (which lets you just create a .elm file and play with elm) was created by Evan the language creator himself. tldr: There's a huge barrier to start playing with clojure that needs to come down and the push needs happen from the top level.
- uDontKnowMe 5y ago
  There is the widely used Luminus framework https://luminusweb.com/ https://luminusweb.com/
  - girishso 5y ago
    Yes, of course and I've got the book as well. The problem with the book is I got stuck on the very first code example in the book. I know there's a forum for the book where (hopefully) I can get my query answered. My point is: these are all individual attempts (the book i mean) and there will always be something on page xyz broken and it can't be solved by individuals. To solve these problems, there needs to be constant time and money investment from someone serious (like facebook in case of create-elm-app).
    - uDontKnowMe 5y ago
      Yes I agree there is a problem of a lack of institutional funding in the Clojure world. Luminus is a great tool but it is a bit sad that it is arguably the most production-ready web toolkit in the ecosystem and it is mostly the work of a single person. There is some community effort to better fund the core infrastructure in Clojure through https://www.clojuriststogether.org/ https://www.clojuriststogether.org/, hopefully they can continue to attract more funding developers and companies. In general a lot of these issues could be alleviated if the community was just in general larger with more contributors. I think the Clojure community is quite welcoming to newbies in the sense that people are quite responsive, kind and helpful around the internet, in Clojurians Slack (try asking there btw, if you haven't yet and are still stuck at the start of the book), etc. But in other ways people seem averse to criticism or suggestions from outsiders. I think the Clojure world needs to do a bit of self reflection to understand why adoption is so low right now and honestly consider what needs to change to attract more developers and contributors.
hcarvalhoalves 5y ago
{:pre [(de/entity? entity)]} is "syntactic sugar" for (hash-map (keyword "pre") (vector (de/entity? entity))) while (.getAttribute mount "data") is calling the method `.getAttribute` on the `mount` object – since it's a Lisp, it's in prefix notation. It also highlights how methods are not special and just functions that receive the object as first argument. Finally, @*post is the same as (deref *post) and the `*` means nothing to the language – any character is valid on symbol names, the author just chose an asterisk. Most of what you believe to be syntax are convenience "reader macros" (https://clojure.org/reference/reader https://clojure.org/reference/reader), and you can extend with your own. You can write the same code without any of it, but then you'll have more "redundant" parenthesis.
- dmitriid 5y ago
  > Most of what you believe to be syntax are convenience "reader macros" And yet, you need to know what all those ASCII symbols mean, where they are used, and they are indistinguishable from syntax. Moreover, even Clojure documentation calls them syntax. A sibling comment provided a wonderful link: https://clojure.org/guides/weird_characters https://clojure.org/guides/weird_characters

cr__ 5y ago

Not sure how you’re supposed to find this page, but it’s pretty useful: https://clojure.org/guides/weird_characters https://clojure.org/guides/weird_characters

dmitriid 5y ago
Nice! I missed it (or it didn't exist) when I last looked at Clojure a few years back
- roenxi 5y ago
  You missed it, it has been there forever. But it says good and bad things about Clojure that its reference documentation is one of its weakest points. The Guide/Reference split obscures a lot of information (do I want guidance on Deps & CLI or do I want reference on Deps & CLI?) and the guides where that gem is hidden randomly mix advanced topics (eg, how to set up generative testing), beginner topics (how to read Clojure code) and library author topics (eg, Reader Conditionals). When you think about it, there is nearly no trigger to look at the guides when the information you need is there. Clojure is a weird mix of both well documented and terribly documented. All the facts are on the website, very few of them are accessible when required. The people who make it past that gauntlet are rewarded by getting to use Clojure.
  - dmitriid 5y ago
    In my case it was even worse, as I started with ClojureScript, and official documentation was simply abysmal then.

ronnier 5y ago

Single engineers will pick clojure at companies , build a project in it, later that engineer will move on, now nobody can maintain this code so it’s rewritten in some normal language. I’ve seen that happen a few times. That code is hard to read and understand. This is why clojure will remain niche.

taeric 5y ago
That is possible with all languages. I've seen java, scala, clojure, perl, python, etc. Usually this is made worse by bespoke build tools and optimizations that make the system punishing to pick up.
- sramsay 5y ago
  You've seen a case where someone wrote something in Python that later devs could not understand and then rewrote it in . . . what? And you've seen that with Java? There's a big difference between a developer going off and writing something in one of the top five most used languages in the world and doing so in Scala.
  - lostcolony 5y ago
    Both are strange and alien to Javascript developers, who can be full stack. Python may seem simple once you know it, but going in blind there's plenty of traps to bite you. Significant whitespace for one.
    - chrsig 5y ago
      I think there's two different issues: 1. picking a language/tool that a company doesn't have personnel with experience using it 2. picking a language/tool that is esoteric, which generally implies #1 as well. #1 on its own isn't great, but generally when sticking in the java/python/ruby/javascript/php/etc...mainstream languages, there's a lot more documentation, and there's a higher chance that _someone_ in the company will have some familiarity. If nothing else, it'd be easier to hire a replacement for.

lvh 5y ago

Minor point of order about the atoms: they're not defined with @ nor derefd with . If you're referring to earmuffs* that's convention not syntax (specifically for dynamically scoped variables, which could be atoms or anything else), and @ is indeed deref. (More specifically @x is a reader macro ish that expands to literally `(deref x)`.)

dmitriid 5y ago
Thank you! I never seem to remember this (but I don't use Clojure, so it's not an ingrained knowledge)

girishso 5y ago

Agreed. These days I'm really fascinated by clojure and trying to learn clojure. Other than the project setup and repl and the editor (which I had considered), these weird characters are throwing me off. What clojure really needs is some kind of opinionated framework or starter template, something like create-react-app. That has all these things figured out so a beginner like me can start playing with actual clojure, which documents all the steps to setup the repl and editor and what not. The last time I asked for this I was told about lein templates, they help but there's no documentation to go with those. There needs to be some push from the top level. create-react-app was produced by facebook. Elm reactor (which lets you just create a .elm file and play with elm) was created by Evan the language creator himself. tldr: There's a huge barrier to start playing with clojure that needs to come down and the push needs happen from the top level.

uDontKnowMe 5y ago
There is the widely used Luminus framework https://luminusweb.com/ https://luminusweb.com/
- girishso 5y ago
  Yes, of course and I've got the book as well. The problem with the book is I got stuck on the very first code example in the book. I know there's a forum for the book where (hopefully) I can get my query answered. My point is: these are all individual attempts (the book i mean) and there will always be something on page xyz broken and it can't be solved by individuals. To solve these problems, there needs to be constant time and money investment from someone serious (like facebook in case of create-elm-app).
  - uDontKnowMe 5y ago
    Yes I agree there is a problem of a lack of institutional funding in the Clojure world. Luminus is a great tool but it is a bit sad that it is arguably the most production-ready web toolkit in the ecosystem and it is mostly the work of a single person. There is some community effort to better fund the core infrastructure in Clojure through https://www.clojuriststogether.org/ https://www.clojuriststogether.org/, hopefully they can continue to attract more funding developers and companies. In general a lot of these issues could be alleviated if the community was just in general larger with more contributors. I think the Clojure community is quite welcoming to newbies in the sense that people are quite responsive, kind and helpful around the internet, in Clojurians Slack (try asking there btw, if you haven't yet and are still stuck at the start of the book), etc. But in other ways people seem averse to criticism or suggestions from outsiders. I think the Clojure world needs to do a bit of self reflection to understand why adoption is so low right now and honestly consider what needs to change to attract more developers and contributors.

hcarvalhoalves 5y ago

{:pre [(de/entity? entity)]} is "syntactic sugar" for (hash-map (keyword "pre") (vector (de/entity? entity))) while (.getAttribute mount "data") is calling the method `.getAttribute` on the `mount` object – since it's a Lisp, it's in prefix notation. It also highlights how methods are not special and just functions that receive the object as first argument. Finally, @*post is the same as (deref *post) and the `*` means nothing to the language – any character is valid on symbol names, the author just chose an asterisk. Most of what you believe to be syntax are convenience "reader macros" (https://clojure.org/reference/reader https://clojure.org/reference/reader), and you can extend with your own. You can write the same code without any of it, but then you'll have more "redundant" parenthesis.

dmitriid 5y ago
> Most of what you believe to be syntax are convenience "reader macros" And yet, you need to know what all those ASCII symbols mean, where they are used, and they are indistinguishable from syntax. Moreover, even Clojure documentation calls them syntax. A sibling comment provided a wonderful link: https://clojure.org/guides/weird_characters https://clojure.org/guides/weird_characters