@jeff.terrell probably not, though I ran into this when I was calling map from a macro which was making use of a helper function to create gensyms, and it's possible that the resulting code would have been problematic. I write macros so very rarely...

Anyone use a clojure based migration tool, or do you just follow simple conventions?

@theeternalpulse We basically built our own Clojure based tool to replace an earlier script&ant based version.

I saw one just called "migrations" on github

I think if we'd been starting that piece of the project after we had adopted Clojure, we'd probably have used one of the existing libraries.

https://github.com/weavejester/ragtime

at least I have a few choices to pick from

I think these are all good enough. thanks for the options

I don't understand what are trade-offs of selecting one of these.

ragtime seems to allow you to specify the commands within edn itself, instead of sql files, which is nice

Yeah, that seems like a nice approach. We've ended up with SQL migrations and code migrations run separately (and manually coordinated). Migratus would have allowed us to integrate that. It also tries to solve the distributed development issue of migrations being added on multiple branches.

It's like our homegrown system -- and that does sometimes require careful coordination and renaming 😐

If we were starting over, I think we'd pick Migratus.

it reminds me a lot of rails migrations, except I've always thought those should be written as sql

migratus does seem to have completeness over simplicity

Today we have about 800 migrations and our system supports dev-only as well as all-tier migrations so we can automate testing data setup as well as general schema changes etc. We've never needed down migrations tho', just up.

my goal is to coordinate some docker containers with compose and up one db container with the migrations

I'm still learning that whole thing so i'm slow to start my project, but it's always something I wanted to learn

the whole deploy coordination stack

I've been using ruby forever and even on non-ruby projects we use capistrano since it's so nice

hi

there are so many cider-jack-in* commands

https://imgur.com/a/ugIPF2h

what are the difference?

don't know, but perhaps the #cider channel might be of some use?

What approach do you feel is better between Mount and Integrant/Duct?

I'm curious about trade-offs of both approaches.

I recommend you write a small webserver app with all 3, Mount, Integrant and Duct

it really doesn't take long, but it should illustrate the differences

Duct is a way to structure web apps with Integrant being one of its opinions.

@mloayzag I've wrote web app with Mount and Pedestal, now I'm reading Duct/Integrant codebase.

I like Mount approach better.

@jaihindh.reddy I've seen Duct only with Integrant. What do you mean by it's opinion?

Duct is a set of opinions on building a web app (much like Luminus), and one of the choices it made is Integrant

Integrant and Component require you to treat namespaces as purely code organisation constructs (which is what they're meant for), and indicate application state explicitly by implementing the protocol(s) and multimethods respectively.

Whereas Mount uses nses for both code organisation and state mgmt.

I found Integrant easiest to understand and the most data-oriented. Haven't built an app with Mount so my opinion is just that, an opinion.

Mount is much less opinionated than Integrant.

Agreed. I was just saying the opinions of Integrant made sense to me.

>Keys in a Duct configuration are expected to initiate into functions that transform a configuration map. There are two broad types: profiles, which merge their value into the configuration, and modules, which provide more complex manipulation. https://github.com/duct-framework/duct#structure What is difference between Profiles and Modules concepts in Duct?

if anything Mount is more opinionated, it forces you to use the namespace system for its own purposes

Integrant is a config map and init functions 🤷

Hi there. What's the tools.deps command equivalent to lein deps? (just resolve and download project dependencies, do not start a REPL, do not start the app).

Is there a recommended way to serialize a Clojure data structure to a string in a way that ensures that it can be deserialized properly at a later point? We’ve tried with prn-str and clojure.edn/read-string, but encountered a problem where the printing would include a tagged literal representing an object, which could not be read by read-string at a later point. I wonder if there’s a standard way to print Clojure data structures that would prevent such things from happening.

https://github.com/clojure-cookbook/clojure-cookbook/blob/master/04_local-io/4-14_read-write-clojure-data-structures.asciidoc

what is the problem you are seeing?

hi. guys, lein doesn't seem to run my test.check test...

lein test

lein test playground.core-test

Ran 0 tests containing 0 assertions.
0 failures, 0 errors.

(ns playground.core-test
 (:require [clojure.test.check :as tc]
           [clojure.test.check.generators :as gen]
           [clojure.test.check.properties :as prop]))

(def sort-idempotent-prop
  (prop/for-all [v (gen/vector gen/small-integer)]
                (= (sort v) (sort (sort v)))))

(tc/quick-check 100 sort-idempotent-prop)

what am I missing?

same with repl...

playground.core=> (clojure.test/run-tests)

Testing playground.core

Ran 0 tests containing 0 assertions.
0 failures, 0 errors.
{:test 0, :pass 0, :fail 0, :error 0, :type :summary}

If you want use it with clojure.test, you have to use defspec: https://github.com/clojure/test.check/blob/master/doc/intro.md#clojuretest-integration

Hi.

I have quite complicated (I believe) data transformation task to perform:

`

{:swagger {:post {:tags                ["resources"]
                    :summary             "Define new resource"
                    ::swagger/parameters {:body ::resource-definition}
                    ::swagger/responses  {201 {:description "Resource created"}
                                          400 {:generate-handler :handle-not-found
                                               :description "Malformed resource definition"}}}
             :get {:tags                ["resources"]
                   :summary             "Define new resource"
                   ::swagger/parameters {:body ::resource-definition}
                   ::swagger/responses  {201 {:description "Resource created"}
                                         400 {:generate-handler :handle-not-found
                                              :description "GET Malformed resource definition"}}}}}
  ;; transform into
  {201 {:post {:description "Resource created"}
        :get {:description "Resource created"}}
   400 {:post {:description "Resource created"}
        :get {:generate-handler :handle-not-found
              :description "GET Malformed resource definition"}}}

using standard clojure reduces it doesn seem very readable and maintainable.

I thought about using spectre, but I know nothing about it - and it requires quite amount of time invested into learning.

Is there anyone familiar with specter, or other similiar utilities, to tell me if this will be doable and I should learn how to do this?

anyone know why the multi-arity version of defn allows an attr-map at the end? are there historical reasons for this? it's apparently merged with the attr-map toward the beginning if it's supplied From the defn docstring: >name doc-string? attr-map? ([params*] prepost-map? body) + attr-map?

I asked Rich this when I discovered it while writing the spec

the idea was that the meta could potentially get large (this pre-dated some of the modern meta and defn syntax) so the idea was to put the meat of the function at the beginning and push the meta to the end, syntactically

I have only ever seen this used once or twice (I found those cases when writing the spec :)

If you have an attr-map in both places, are they merged?

(I guess I could easily test that in the REPL but figured you might answer faster 🙂 )

Answer: yes.

user=> (defn ^:foo foo {:bar 13} ([x] (* x x)) {:quux 42})
#'user/foo
user=> (meta #'foo)
{:bar 13, :ns #object[clojure.lang.Namespace 0x4fed80ad "user"], :name foo, :file "NO_SOURCE_PATH", :column 1, :line 5, :foo true, :quux 42, :arglists ([x])}
user=> 

Thanks, Alex!

> the idea was to put the meat of the function at the beginning and push the meta to the end, syntactically If that was the motivation, why keep the attr-map at the beginning as well? For backward compatibility?

I'd assume so, RH has strong opinions about compatibility

Hey folks, how do we sign up for jira? I tried creating an account, but all I get is “Your email address <mailto:[email protected]|[email protected]> doesn’t have access to http://clojure.atlassian.net”

if you are looking just to vote or comment tickets, I'd ask that you wait as we are working on something new for that. if you're looking to add a new ticket, you can do that at https://clojure.atlassian.net/servicedesk/customer/portal/1 without an account. if you're looking to do work on tickets, provide patches, etc, you should fill out the CA at https://clojure.org/dev/contributor_agreement and then request an account at the same portal

and https://clojure.org/dev/dev is the doc for the above

got it - i got to the jira through https://clojure.org/dev/creating_tickets which doesn’t mention the service desk piece - thanks!

Does this exception make sense to folks?

java.lang.ClassCastException: com.badlogic.gdx.physics.bullet.collision.SWIGTYPE_p_p_btCollisionObject cannot be cast to com.badlogic.gdx.physics.bullet.collision.btCollisionObject

no

swig is a tool for generating java bindings to c code

my first guess would be the SWIGTYPE class is the class generated by the swig tool, and the non-swig type is a wrapper class to make it easier to use

you can even find generated java docs for the swigtype if you google it (the docs are pretty empty)

http://javadox.com/com.badlogicgames.gdx/gdx-bullet/1.3.1/com/badlogic/gdx/physics/bullet/collision/SWIGTYPE_p_p_btCollisionObject.html

Ah okay, so it's very possible the wrong kind of object is being instantiated to be compared against?

This is happening in a when block, so perhaps a special case for the SWIG?

no

you are trying to do something with the swig type that you can only do with the non-swig type

the type error is exactly that, the jvm saying this type you are trying to pass to some method doesn't match the signature of the method

the rest of the stacktrace will tell you which method