Clojurians Log v2

New prerelease of Clojure CLI 1.10.3.875: • New: support for specifying multiple functions with -X with -> semantics • https://clojure.atlassian.net/browse/TDEPS-182 - Improve deprecation message to be more accurate • https://clojure.atlassian.net/browse/TDEPS-183 - Fix -Sdescribe output to be valid edn on Windows • https://clojure.atlassian.net/browse/TDEPS-179 - Fix incorrect classpath when :classpath-overrides removes path

Awesome! Can you point me to an example of how that new -X stuff works? Is it literally just -X:myalias foo.bar/fn1 foo.bar/fn2 some.other/thing and each should take a hash map and return a hash map?

yes

What happens if any of them return nil? Does exec just pass the original input hash map into the next function, or does it end up passing nil?

well importantly, the first function gets the kvs from the exec-args/ cli

it's like ->, so if one function returns nil, the next gets nil

Ah, so that also means that the functions in the 2nd pos on don’t need to take hash maps, right? It could be any data produced from the earlier fns?

I suppose :)

I will not claim that this is fully baked yet, so I reserve the right to change my answer before it becomes a stable release :)

(I’m already imagining how folks like @borkdude might think of abusing this 🙂 )

evil chuckle

that seems really interesting

with low startup time that makes bash very close to a useable repl

repls are also very usable repls :)

haha very true 🙂

> -X:myalias foo.bar/fn1 foo.bar/fn2 some.other/thing how does it know that it's (-> {} foo.bar/fn1 foo.bar/fn2 some.other/thing) and not (foo.bar/fn1 {'foo.bar/fn2 'some.other/thing}) ?

@seancorfield could you help me understand how I could abuse this? ;)

symbols at the front are functions

and @dpsutton about startup time: how does this solve startup time?

fn* [kpath v]* map?

i was thinking about sci/bb but at that point you could just pass in forms to be evaled

ah, so clj-exec first consumes all symbol args as fn chain, and then rest args as map arg?

well we now have trailing map support ala 1.11 too

> fn* [kpath v]* map? this is great explanation 😄

https://github.com/clojure/brew-install/blob/1.10.3/src/main/clojure/clojure/run/exec.clj#L100

to be more precise

parsing is done with that spec

Just tried it out on pwsh, it works

but of course :)

not sure how I feel about the -X threading

thanks :)

I tried this:

clj -X clojure.core/pr-str clojure.core/read-string clojure.pprint/pprint :a 1

interested in feedback, so do more , and come back

intuitively I wanted to write this:

clj -X clojure.pprint/pprint clojure.core/read-string clojure.core/pr-str :a 1

(clojure.pprint/pprint (clojure.core/read-string (clojure.core/pr-str {:a 1})))

I don't know that this is something you're going to want to use all the time, but it is another dimension of composition available

the goal is not to replicate the repl. if you want that, use a repl

mm yeah...

I guess my big test is going to be breaking depstar up into multiple -X-compatible functions so you can run parts of it or all of it in a pipeline 🙂

if you do do that, I would be very interested in hearing your questions/feedback. if I may be so bold, that might be a better thing to do in design space before actually cutting the code :)

Okay, another argument why (fn1 (fn2 argmap)) might make sense:

PS C:\Users\Vlaaad\Projects\deps-test\lib> Get-Content .\deps.edn
{:aliases {:deploy {:ns-default deploy}}}
PS C:\Users\Vlaaad\Projects\deps-test\lib> Get-Content .\src\deploy.clj
(ns deploy)

(defn dev [args]
  (merge
   {:env :dev
    :url "dev-cluster"}
   args))

(defn prod [args]
  (merge
   {:env :prod
    :url "prod-cluster"}
   args))

(defn deploy [env]
  (prn :deploy env))

PS C:\Users\Vlaaad\Projects\deps-test\lib> clj -X:deploy dev deploy :a 1
:deploy {:env :dev, :url "dev-cluster", :a 1}

PS C:\Users\Vlaaad\Projects\deps-test\lib> clj -X:deploy deploy dev :a 1
:deploy {:a 1}

Oh, definitely. I need to tease apart the various useful processes that depstar performs and figure out exactly what inputs and outputs each of them have.

I have smaller things to test it on before that 🙂

I don’t understand this at all. -> says “do things in this order” and that’s exactly what I would expect: setup the env, run the command.

the key thing is that inputs/outputs need to align, which harkens to namespaced keys ... but those fight with conciseness of what you want at the CLI

agreed, the order is the most important thing here

so it's more like clj -X:build clean jar than clj -X:build deploy dev ?

yes

clojure -X:depstar sync-pom compile jar for example 🙂

mm yeah, that makes a lot of sense

@alexmiller What’s the thinking around -X functions that would require (shutdown-agents) calls at the end to avoid the 60 second “hang”? That’s been a long-standing issue with -main functions. I didn’t check the latest exec source but does it handle that? (since you clearly cannot chain exec functions that call shutdown-agents)

Haven’t thought about it

I just looked at the exec.clj code and it does not call (*exit* 0) or (shutdown-agents) in the “happy” case…

Yeah, my first test of chaining tasks leads to a 60 second hang at the end because of that.

(I used to run the tasks individually and they had calls to (shutdown-agents) at the end — which I removed so I could chain them — and I can’t just call clojure.core/shutdown-agents via -X because it takes no arguments 😞