I recommend either: • The official Java API • https://github.com/cognitect-labs/aws-api

the latter is very nice from clojure, but it’s been around a lot shorter than the official API (like a year or so)

thank you, @U07S8JGF7! i’ll take a look.

that cognitect-labs library looks great! now i need to figure out how to use a custom profile with this and it’ll be fun 🙂 thanks again!

there's also Amazonica: https://github.com/mcohen01/amazonica

I do not recommend amazonica.

@U07S8JGF7 why not?

It wraps the official java lib, exposes renamed methods via reflection, and does so in a way that doesn't allow access to the underlying client object.

In addition, all interactions with it are variadic named args, meaning that it doesn't even expose a good data-oriented API.

IOW - it takes away some value (exposing the client is useful!) and the only value it adds is renaming args and using keywords. IMO it's basically a vanity lib ("I want to type what I want to type.")

Good reasons. Thanks for the explanation

i had seen Amazonica but as a noob it was difficult to get started with compared to Cognitect’s aws-api (which has been a lot of fun to play with.)

Likewise a beginner myself - but I think having a function that transforms {"firstname" "Joe"} to {:firstname "Joe"} - is not the worst thing provided you check that - "Joe" is indeed a string - I think validating any user input is a good place to use spec

On that note, I use this little fn to “clojurise” JSON keys: https://github.com/pmonks/fake-tweets/blob/master/src/fake_tweets/core.clj#L17-L26 It can be used directly with Cheshire (JSON parsing lib) like this: https://github.com/pmonks/fake-tweets/blob/master/src/fake_tweets/core.clj#L77-L78 One thing to note is that it doesn’t handle conflicts e.g. a JSON object with keys “firstName” and “first_name” (which is arguably poor JSON schema design, albeit technically possible).

keywords are kept in a weak hash for interning (so that two keywords that are equal are the same object), before it was a weak hash there was a memory problem with making large numbers of keywords

it does not even matter in which namespace you calling it

/tmp/whatever 
 ✔  lein repl
nREPL server started on port 54745 on host 127.0.0.1 - 
REPL-y 0.4.4, nREPL 0.6.0
Clojure 1.10.0
Java HotSpot(TM) 64-Bit Server VM 1.8.0_202-b08
    Docs: (doc function-name-here)
          (find-doc "part-of-name-here")
  Source: (source function-name-here)
 Javadoc: (javadoc java-object-or-class-here)
    Exit: Control+D or (exit) or (quit)
 Results: Stored in vars *1, *2, *3, an exception in *e

user=>

do you not get something like this eventually?

(I also have the nprel server stuff)

hi, I got something like:

➜  scratch lein repl

Java HotSpot(TM) 64-Bit Server VM warning: Options -Xverify:none and -noverify were deprecated in JDK 13 and will likely be removed in a future release.
nREPL server started on port 54972 on host 127.0.0.1 - 
Tried to use insecure HTTP repository without TLS:
 sona: 
 slingshot/slingshot/0.10.3/slingshot-0.10.3.jar

This is almost certainly a mistake; for details see

Reading the faq.md ING.

And just updated project.clj file as instructed in FAQ.md.

It's just like taking forever for the script to continue...always stuck on on the line of launching server.

can you try this in a temp folder without a project.clj file?

mkdir /tmp/foo && cd /tmp/foo && lein repl

Ok

Now my zsh complains..Maybe something wrong with my lein setup, I'll double check it

zsh: command not found: lein

@dpsutton Thanks for your patience lol

weird. how did your path break

lol. no worries

Last time I did not follow lein's official page for install instruction, just borrow the quick set up from tutorial [Learning Clojure from ground up](https://aphyr.com/posts/301-clojure-from-the-ground-up-welcome)

Now I'll just try to follow the homebrew way

yeah just install lein so that its on your path. brew or the official instructions

Is it normal to take such long time to use user=> prompt?

➜  foo lein repl
Java HotSpot(TM) 64-Bit Server VM warning: Options -Xverify:none and -noverify were deprecated in JDK 13 and will likely be removed in a future release.
nREPL server started on port 56115 on host 127.0.0.1 - 

somehow still stuck on the sever prompt after brew it

it should be quite speedy

what is lein --version

and java -version

[1]  + 75363 suspended  lein repl
➜  foo java --version
java 14.0.1 2020-04-14
Java(TM) SE Runtime Environment (build 14.0.1+7)
Java HotSpot(TM) 64-Bit Server VM (build 14.0.1+7, mixed mode, sharing)
➜  foo lein --version
Java HotSpot(TM) 64-Bit Server VM warning: Options -Xverify:none and -noverify were deprecated in JDK 13 and will likely be removed in a future release.
Leiningen 2.9.3 on Java 14.0.1 Java HotSpot(TM) 64-Bit Server VM
➜  foo

java 14 might not be the best

you could try java 13

or alternatively try brew install clojure/tools/clojure

which will install the clj and clojure cli tools

Looks like i already got clojure installed before lein

➜  foo which clojure
/usr/local/bin/clojure
➜  foo brew install clojure/tools/clojure
Updating Homebrew...
Warning: clojure/tools/clojure 1.10.1.536 is already installed and up-to-date
To reinstall 1.10.1.536, run `brew reinstall clojure

So my only option left is either downgrade java14 to 13 or have multiple version of java?

i don't know

i'm not sure if lein is compatible with java 14

Oh I see

What's your setup for running lein environment?

The official doc of lein said : OpenJDK version 8 is recommended at this time.

I'll try that

i think i use java 8 or 11 or 13 depending on computer

@dpsutton Thank you so much sutton! You've being really helpful 🙂

for sure

I run everything on OpenJDK 14 locally, including lein

(I was on lein 2.9.1, updating to 2.9.3 to double-check)

oh interesting. thanks for confirming sean. no idea what's going on here then

Updated to 2.9.3 and everything still works on OpenJDK 14

(! 547)-> java --version
openjdk 14 2020-03-17
OpenJDK Runtime Environment (build 14+36-1461)
OpenJDK 64-Bit Server VM (build 14+36-1461, mixed mode, sharing)

Thu May 14 08:37:06
(sean)-(jobs:0)-(~/cfml)
(! 548)-> mkdir /tmp/foo && cd /tmp/foo && lein repl
OpenJDK 64-Bit Server VM warning: Options -Xverify:none and -noverify were deprecated in JDK 13 and will likely be removed in a future release.
nREPL server started on port 62294 on host 127.0.0.1 - 
REPL-y 0.4.3, nREPL 0.6.0
Clojure 1.10.0
OpenJDK 64-Bit Server VM 14+36-1461
    Docs: (doc function-name-here)
          (find-doc "part-of-name-here")
  Source: (source function-name-here)
 Javadoc: (javadoc java-object-or-class-here)
    Exit: Control+D or (exit) or (quit)
 Results: Stored in vars *1, *2, *3, an exception in *e

user=> Bye for now!

Thu May 14 08:37:30
(sean)-(jobs:0)-(/tmp/foo)
(! 549)-> lein version
OpenJDK 64-Bit Server VM warning: Options -Xverify:none and -noverify were deprecated in JDK 13 and will likely be removed in a future release.
Leiningen 2.9.1 on Java 14 OpenJDK 64-Bit Server VM

Thu May 14 08:37:34
(sean)-(jobs:0)-(/tmp/foo)
(! 550)-> lein upgrade
The script at /Users/sean/bin/lein will be upgraded to the latest stable version.
Do you want to continue [Y/n]? 

Upgrading...
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   137  100   137    0     0    321      0 --:--:-- --:--:-- --:--:--   321
100 13413  100 13413    0     0   7649      0  0:00:01  0:00:01 --:--:-- 57566
Downloading Leiningen to /Users/sean/.lein/self-installs/leiningen-2.9.3-standalone.jar now...
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   637  100   637    0     0   1529      0 --:--:-- --:--:-- --:--:--  1527
100 13.9M  100 13.9M    0     0  2448k      0  0:00:05  0:00:05 --:--:-- 3074k
/Users/sean/.lein/self-installs/leiningen-2.9.3-standalone.jar.pending: OK
OpenJDK 64-Bit Server VM warning: Options -Xverify:none and -noverify were deprecated in JDK 13 and will likely be removed in a future release.
Leiningen 2.9.3 on Java 14 OpenJDK 64-Bit Server VM

Thu May 14 08:37:50
(sean)-(jobs:0)-(/tmp/foo)
(! 551)-> lein repl
OpenJDK 64-Bit Server VM warning: Options -Xverify:none and -noverify were deprecated in JDK 13 and will likely be removed in a future release.
:repositories detected in user-level profiles! [:clojars] 
See 
nREPL server started on port 62326 on host 127.0.0.1 - 
REPL-y 0.4.4, nREPL 0.6.0
Clojure 1.10.0
OpenJDK 64-Bit Server VM 14+36-1461
    Docs: (doc function-name-here)
          (find-doc "part-of-name-here")
  Source: (source function-name-here)
 Javadoc: (javadoc java-object-or-class-here)
    Exit: Control+D or (exit) or (quit)
 Results: Stored in vars *1, *2, *3, an exception in *e

user=> 

Maybe IP6 vs IP4? Or maybe something bad in ~/.lein/profiles.clj ?

@hesiyun1996 What's in your ~/.lein folder?

Particularly, what's in your ~/.lein/profiles.clj file? That's often what breaks Leiningen (and why I wish more tutorials would recommend the official Clojure CLI tools instead of a) Leiningen and b) adding weird stuff to the profiles.clj file 😞 )

@U04V70XH6 Thanks for the follow up

@U04V70XH6 Looks like I don't have ~/.lein/profiles.clj file

➜  foo cat ~/.lein/
repl-port       self-installs/

@U04V70XH6 @dpsutton I finally resolved the issue...I am using emacs as my editor. And magically after i set up [cider:The Clojure Interactive Development Environment that Rocks for Emacs]( https://github.com/clojure-emacs/cider), the lein repl command works as it should be

@U04V70XH6 @dpsutton My best guess is that somehow the emacs-clojure library solves the issue of clojure in emacs env setup? But, thanks you guys helping along the way 🙂

finally worked lol

That sounds unlikely. CIDER just invokes lein as seen by the “startup command” in your repl. I see there’s an “x” at the beginning of your project.clj form. Is that an errant typo?

Maybe someone can add an example of that to http://clojuredocs.org/clojure.core/format

Perfect! Thank you @U04V70XH6

Under the hood, it's this https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/util/Formatter.html

Especially now that v1.10 is JDK 8+ only. I assume it’s just a matter of time & priorities for this to happen? If Cognitect were to sketch out the desired interface (albeit the hard part), would they accept implementations from the community?

given that that's not the hard part, not sure that's a likely sequence of events

I've been doing a ton of file interop lately so starting to form some opinions but not likely to be an area we work on "soon"

I think we'd probably want to take a light touch to anything in core (you can always augment with libs) so figuring out what's even in scope is problem 0

Right. And it would be ideal if the interface was at least somewhat portable to other runtimes (CLJS, Joker, etc.).

And FWIW by “hard part” I meant that public interfaces are hard because of politics / stylistic / future-proofness / portability considerations, not because they’re technically hard to write down…

I got that :)

fyi, the http://clojure.java.XYZ namespaces are not designed to be portable (that's why they say "java")

Of course

Java's historical legacy wrt File and Path is a huge pain and is probably the biggest complicating factor

Oh I know - I’ve been doing Java since 1997. 😉

Well I did - I no longer consider myself a Java guy since switching to Clojure. 😉

there are so many nice things buried in the Paths and Files stuff now, it's irritating how often you have to change between those contexts

@U0MDMDYR3 and don't forget that the first step in contributing is to sign the CA and get yourself on this list https://clojure.org/dev/contributors 🙂

A task comes first, then a patch for that task that I think’s worth submitting, then the CLA. 😉

(I know that's not really the first step and not all types of contributions actually require a signed CA but 🙂 )

And there’s no way I’d go near this with a 40' barge pole without an interface definition that’s blessed by Cognitect. Too much risk of it being a complete waste of time…

there actually is a jira for adding Path support already

specifically for jio/file but that part at least is in the tracker

(that’s not a slam on Cognitect btw - I wouldn’t be happy for randos to define supported public interfaces for my code either)

@alexmiller I’ll check it out, and if there’s an interface definition (however draft it might be) might have a crack at an impl too.

I’ve been doing some scripting type work, and not having portability between Joker and, say, Planck has been a bit of an annoyance.

Plus my Clojure knowledge is 99.97% based on CLJ, so figuring out translations from CLJ API to Joker or Planck or whatever is also a friction point.

I haven't looked at the ticket, I just know it exists

I’ll see if I can find it.

https://clojure.atlassian.net/projects/CLJ/issues/CLJ-2333 I think.

And it already has a patch. 😉

yeah, really just the tip of the iceberg

@U0121PUL58W there sure is, I've been using babashka for these sorts of things

https://github.com/borkdude/babashka

there's a #babashka channel for people who use it

it's a quick clojure interpreter that's built for scripting

Use ClojureScript (requires node runtime), babashka, or compile to native using GraalVM. Basically don't use the JVM, otherwise you will be dependent on JVM startup time as well as Clojure classloading time.

I just found this as I said this: https://stuartsierra.com/2019/12/21/clojure-start-time-in-2019

babashka looks very cool

Thanks!

you're welcome

"It is better to have 100 functions operate on one data structure than to have 10 functions operate on 10 data structures." - Alan Perlis

If you are using the Clojure CLI tools, e.g. clj and/or clojurecommands with a deps.edn file, it has its own separate cache of precomputed classpaths that often cache file name paths to files inside your .m2 directory. Using the -Sforce option should force it to recompute those paths.

Installing the Clojure CLI tools does not install anything in your .m2 directory.

In case it clarifies my earlier statement: Running clj or clojure commands can cause files to be added to your .m2, but installing the Clojure CLI tools by itself does not.

clj -Sforce will force a re-download of libs

Not sure how best to reinstall Clojure CLI on Windows - sorry!

Been a looooooong time since I used Win. 😉

As mentioned earlier, you may find that unless you use -Sforce on later clj /`clojure` commands, you may get errors about missing classes. This can happen if the later clj / clojurecommand uses a cached classpath stored in a file inside the .cpcache directory that gives a full path to a file that was recently removed from .m2

Right. Or I just whack .cpcache too

that also does it

Although for a single user account there is one .m2directory, but there can be any number of .cpcachefiles strewn all over the place.

Right, though I happen to have a well defined root directory for all of my development, and I could just run something like find $DEV_ROOT_DIR -type d -name .cpcache -exec rm -r '{}' \; to clear things.

But very good to know that .cpcache has references into .m2.