thank you clojure for always trying to use data to solve problems. any time i have to go into another language i find myself reimplementing “data as a first class citizen” everywhere, and it saddens me. forever

@punit-naik That would be more on-topic in #aws but I don't know how active that channel is. Since the question isn't about Clojure, it doesn't belong in this channel -- #off-topic would be a safe place to ask, with plenty of people in it.

okay

Public apology to @punit-naik for pushing him to other channels -- I totally missed he was asking about a specific Clojure library and thought he was asking about AWS Console stuff. My bad!

In clojure How can I set the parquet compression algorithm to gzip?

Is it by default gzip?

What are you trying to do?

@nayudu.sushma Are you trying string compression? as in RLE or something ?

hi all, i'm trying to hash a clojure map such that regardless of the order of the keys the hash is the same

(-> {} (assoc :a 1) (assoc :c 2)) ;; {:a 1 :c 2} (-> {} (assoc :c 2) (assoc :a 1)) ;; {:c 2 :a 1}

any ideas?

(= (-> {} (assoc :a 1) (assoc :b 2) hash) (-> {} (assoc :b 2) (assoc :a 1) hash)) is true

you're already covered

note the hash calls on each

Hi, i have come with one issue on my test.

(clojure.test/is (= 5) {:test "fail"})

true

Can anyone check this behaviour? Or have anyone encountered before?

(= 5)will return true!

tests normally return a good message about why they failed. if you are seeing a failure, let that bubble up rather than the uninformative override you've got with {:test "fail"}

(is (= 5) nil)will also return true.

not in my machine

What you need is (is (= 5 (other-equality-condition))

(clojure.test/is (= 5) nil)

ERROR in () (form-init1777224899660398758.clj:1)
expected: (= 5)
  actual:
     clojure.core/eval   core.clj: 3105
                   ...
dev-platform/eval52764  REPL Input
java.lang.Exception: = expects more than one argument
nil

@jimenezsaezjoseantoni (require '[clojure.test :as test]) (test/is (= 5) nil)`

(require '[clojure.test :as test]) (test/is (= 5) nil)
nil

ERROR in () (form-init1741981829714996247.clj:1)
expected: (= 5)
  actual:
     clojure.core/eval   core.clj: 3105
                   ...
dev-platform/eval52758  REPL Input
java.lang.Exception: = expects more than one argument
nil

@jimenezsaezjoseantoni Interesting results, not sure why that is the case!

can you just eval (= 5) without any test assertion?

that will return true

user=> (= 5)
true

i think the problem is realted to is macro

related

This should mostly work (is (= 5 (other-equality-condition))

Yes, the problem for me is, that by mistake you write (is (= (large-expression-large-large)) (other-large-large-large-expression)) instead of (is (= (large-expression-large-large) (other-large-large-large-expression)))

Both expression are going to give true

even when you made a mistake

in the worse case you have a false true

oh. well, yeah you have to make sure you test what you want to test

I am sure, but what if by mistake you don't notice this, the test will pas silently

@jimenezsaezjoseantoni you need two separate is to test two separate expressions. The usual syntax is (is (predicate test expr)) `

so one thing to do is not use = but instead use a function that has a definite arity of two. so if you made the mistake it would error

(is (consistent (user-counts info) 5))) or something like that

it can be 1 arity also for instance (is (keyword? expr))

Is just exists to have better reading tests and automation.

I found out what's going on. https://github.com/venantius/ultra

that looks like a feature for you then, right? don't you want to prevent the testing of (= 4)?

yeah

(throw (Exception. "= expects more than one argument")) i'm surprised this didn't show up then

Is there a way to use datasets in clojure and postgres for tests with dynamic data? I managed to use xmls to populate the database but I was not able to use clojure functions in it to hava dynamic data (like today date for a column for example)

I have another project with clojure and datomic where I use edn files but when it comes to postgres I found nothing 😕

@dominicm see above, it's in the snippet, a call to s/valid?

Just wanted to make sure 🙂

@skrat the error could be in :survey/status?

@dominicm thanks for looking, I found the issue, it was this AOT thing again, when the .clj and .class files in uberjar have the same timestamps

I’m working with spec right now. Want to catch/parse the value which ends with * (for my regex parser) Currently something like this doesn’t work -> (s/cat :base ::base :star #"\*") Any ideas? The regex matchign doesn’t seem to work and I don’t know how to make string match in spec.

@denisgrebennicov you should call seq on the string before passing it in

See https://juxt.pro/blog/posts/parsing-with-clojure-spec.html and https://gist.github.com/thegeez/77aee6f0ebcf6a42aa7d893388502e40

I tend to use my emacs cider eval more than I use the repl buffer, is there any benefit to a workflow by using the repl in tandem with eval'ing in a buffer directly, or completely using the repl. I'm just not seeing it as convenient.

Still confused, why something like this doesn’t work

(s/def ::base #"[a-zA-Z]")
(s/conform ::base (seq "a"))

tried with and without quotes for regex

write not I get

java.util.regex.Pattern cannot be cast to clojure.lang.IFn

why do you think it would work?

spec is not built around regexes, it is built around predicates

none of the spec docs or examples indicate you can use a regex

https://clojure.org/guides/spec#_entity_maps has maybe the closest example, it shows using a regex and re-matches to build a predicate for spec

@hiredman anyway. What I want is match only single letter. I don’t want s/* or s/+, just single one. Still confused on how to achieve that.

(fn [letter] (fn [input] (= letter input)))

or just (partial = letter)

or #{letter}

why aren't you looking at instaparse?

instaparse is actually built as a parser of strings, and will let you define terminals as regexs

if you want to match any character char?is the predicate

if you turn a string in to a seq of characters, you cannot use java regexes on them, because regexes only match strings, but spec can only do parsing kind of things on a string if you turn it in to a collection of characters

Anyone?

@denisgrebennicov I’ll second @hiredman - if you want to parse, use instaparse, not spec

I'm gonna submit a patch to Clojure spec that automatically calls (println "You should use instaparse") whenever a regex spec is used to parse characters of a string

Endorse

Hey folks - is there a quick way to de-duplicate a sequence by a (sorted) key? e.g. given [{:key 'a' :data 'apple'} {:key 'a' :data 'apple'} {:key 'b' :data 'banana'}] return a sequence of just the first and last (`apple` and banana) hashes?

The only way I can think of to de-dupe a sequence is to put all the values in a set (or hash) but I want something that can work more simply on a sorted sequence

distinct-by is something I’ve often sorely missed in core

https://crossclj.info/fun/medley.core/distinct-by.html

(distinct-by :key ordered-sequence)

nice - at least I can steal that code 🙂

yeah

it’s just a knock-off of distinct if you view the clojure source 😛

but nice since it returns a transducer and all

I’d forgotten distinct - that would probably work for me, though I worry a bit about how efficient it is. My non-unique entries are probably identical - I just assumed it’d be more efficient to compare keys than the whole object.

(and distinct loses any benefits of knowing the sequence is sorted)

deduplicate is available if you just want to drop contiguous entries

dedupe*

but I wouldn’t assume that checking a key is more efficient than the whole map

persistent data structures make whole object comparisons pretty cheap afaik

@rutledgepaulv thanks for dedupe. Sigh. My ability to search the cheat-sheet is pretty poor tonight, it seems.

np!

any timeline on the prem -> cloud migration tool?

> If you are working on committed code with no local deps you will get a stable revision named after your commit.

what if the local deps are in the same git repo? ^^

hah wrong channel

Problem that knowing clojure solved for my java project

L

:

We get events as xml passed through query parameters to a url

and its involved xml too

my god clojure saved my ass on parsing

does anyone know of a reason why trying to key into a map with a known existing key (with value) would return nil? e.g. the map prints like {:foo 1 :bar 2} but (:foo that-map) evaluates to nil

I found someone having a similar issue with a sorted-map, but mine is not

@jeremyraines That sounds quite unusual to me. Could there be issues with non-ASCII characters being used in the keywords involved?

if you literally mean print as, it could be ":foo"

i checked that it’s actually a keyword

(and using prn instead of print / println will make that clear)

OK

@andy.fingerhut I suspect this might be the case. It’s on a result of using the csv-map library. But I’ve tried what I can think of to expose hidden characters, copied the whole file as plain text to a new file, etc

Maybe something like (map int (str <my-keyword-expr>)) on the one in the map, and the one you are trying to search for, would be a good way to find out if there are funny chars involved.

ok

The issue you mention with not finding a key in a sorted map could be due to using a custom comparator function that is not correct. This article might help determine if this is the case: https://clojure.org/guides/comparators

or also check the type of the map, not just the printing, and call keys on the map, and check the type of all the keys

a map containing the string ":foo" as a key will println like {:foo 1} but prn like {":foo" 1}

csv-map looks pretty questionable if https://github.com/mihi-tr/csv-map is it

andy’s suggestion to map the chars of the (str kw) seems to reveal that it is a hidden character — thanks @andy.fingerhut

still a bit baffled because I’ve even tried deleting the header row and typing it out by hand, but this puts me on the right track I think

@hiredman yeah that’s the one

pretty light wrapper over clojure.core/parse-csv

there is no clojure.core/parse-csv

or rather clojure.csv

https://github.com/davidsantiago/clojure-csv

https://github.com/mihi-tr/csv-map/blob/master/src/csv_map/core.clj this beyond light

it was a Byte Order Mark, can be removed in Vim with :set nobomb