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2021-04-13
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Michael Stokley01:04:10

I'm trying to programmatically create a union type out of an existing spec and a new spec. i understand this is a complete hack, but i've tried many variations of the following:

(defonce spec-ledger (atom {}))

(defn add-to-ledger!
  [k spec]
  (swap! spec-ledger update k (fnil conj #{}) spec))

(defn union-spec
  [k spec]
  (let [existing (get @spec-ledger k)
        options  (->> spec
                      (conj existing)
                      (map-indexed (fn [i p] [(keyword (str i)) p]))
                      flatten)]
    ;; return quoted form instead of evaluating because this evaluates to an
    ;; object, which can't be "embedded in code"
    `(s/or [email protected])))

(alter-var-root
 #'clojure.spec.alpha/def-impl
 (fn alter-sdef-impl [sdef-impl]
   (fn register-union-spec-instead
     [k _form spec]
     (add-to-ledger! k spec)
     (let [union              (union-spec k spec)
           ;; can't seem to call `s/def` directly here
           ;; but in order to call `s/def-impl`, need to need to generate
           ;; updated `form` and `spec` (which `s/def` would otherwise
           ;; accomplish)
           [_ _ form' spec'] (macroexpand `(s/def ~k ~union))]
       (sdef-impl k (eval form') (eval spec'))))))
this ultimately fails when it sees the output of, for example, s/or presumably because it's an object. (`Can't embed object in code, maybe print-dup not defined: [email protected]`)

Michael Stokley01:04:39

folks are suggesting s/form to go from an object to a form

Michael Stokley01:04:32

are there other strategies (other than getting rid of my existing specs or getting rid of my non-conforming data) that jump out at folks?

Eric Ihli01:04:35

What's a good way to track down what line of my code is causing a stackoverflow? I'm only getting it when I work with a really big data set. So I don't think it's an infinite loop as part of some calculation. The biggest problem I'm having debugging it is that the lines in the error are all from clojure namespaces.

LazySeq.java:   42  clojure.lang.LazySeq/sval
              LazySeq.java:   51  clojure.lang.LazySeq/seq
                   RT.java:  531  clojure.lang.RT/seq
                  core.clj:  137  clojure.core/seq
                  core.clj: 2927  clojure.core/drop/step
                  core.clj: 2932  clojure.core/drop/fn
              LazySeq.java:   42  clojure.lang.LazySeq/sval
              LazySeq.java:   51  clojure.lang.LazySeq/seq
The function that I call that triggers it is about 100 lines long and kind of ugly but it's got a top-level loop/recur and I don't recur by calling the function. My best guess now is to keep placing Thread/sleeps and printlns and step through the code. But with a sleep of 10ms I just watched it run for about 5 minutes and all of the output looked fine. If I uncomment the commented out sexp below, that's when I get the stackoverflow.
(def tightly-packed-trie
  (let [tight-ready-trie
        (->> trie
             (map (fn [[k v]]
                    (let [k (map #(get trie-database %) k)]
                      [k v])))
             (into (trie/make-trie)))]
    #_(tpt/tightly-packed-trie
     tight-ready-trie
     encode-fn
     decode-fn)))
That function in it's current state is at https://github.com/eihli/clj-tightly-packed-trie/blob/main/src/com/owoga/tightly_packed_trie.clj#L225

Michael Stokley01:04:12

with lazy stuff like this, try mapv instead of map

Michael Stokley01:04:52

i've had good experiences getting better stack traces doing so

Eric Ihli01:04:03

Hm. I'm iterating over a custom datatype and I guess I'm not implementing what I need to in order to use mapv yet. Method com/owoga/trie/Trie.iterator()Ljava/util/Iterator; is abstract

Michael Stokley01:04:47

there are other ways to realize a lazy sequence

Eric Ihli01:04:57

Thanks for the idea. I think it's a good lead. I haven't made any progress with it yet though. I noticed http://clojure.github.io/clojure/clojure.stacktrace-api.html and thought I could get all traces rather than just what my editor was showing me. But that's still not showing anything other than core clojure code.

Eric Ihli01:04:25

Ah ha ha... -XX:MaxJavaStackTraceDepth=-1

Eric Ihli01:04:10

Bingo. You were right. Adding a doall to a concat fixed it I think. And that stacktrace pointed straight to the line.

ūüôŹ 3
Michael Stokley02:04:20

i've heard folks say never to use concat instead of into for that reason

Edward Ciafardini02:04:15

newb question: Just getting my feet wet with clojure....every time I run any lein commands, I get this warning: 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. 1. Does this matter? && 2. How do I make it stop?

hiredman02:04:55

It doesn't matter a ton at the moment, upgrading your lein version might make it go away

hiredman02:04:12

Lein passes (passed?) those options to speed up jvm launching, lein because of the way it works usually ends up launching two

Sebastian Ohlsson07:04:25

Hi there! How do I run a python script with sh ?

sb07:04:17

I dont know what is the goal at your side, maybe wrong idea

Sebastian Ohlsson08:04:12

Thanks for the feedback! Due to only calling a python script one time I think its overkill to add another library and would rather try to learn to sh it. I tried the second suggestion

(use '[clojure.java.shell :only [sh]])
(sh "python3" "helloworld.py")
But I got the following result:
(sh "python3" "helloworld.py")
=>
{:exit 9009,
 :out "",
 :err "Python hittades inte. Kör utan argument för att installera från Microsoft Store eller inaktivera den här genvägen från Inställningar > Hantera alias för körning av program.\r
       "}
The error is essentially "python wasnt found."

sb08:04:49

I don’t have experience w/ Windows. On mac, works fine:

user=> (use '[clojure.java.shell :only [sh]])
nil
user=> (sh "python3" "hello.py")
{:exit 0, :out "hello world\n", :err ""}
user=> (sh "python" "hello.py")
{:exit 0, :out "hello world\n", :err ""}

zackteo08:04:33

Whoops, I realised you want to specifically call python are you on windows or linux?

Sebastian Ohlsson08:04:00

Hello! Yes I started looking at the docs but sadly I am no wiser. I am on windows

zackteo08:04:22

is your helloworld.py the right path? Perhaps you might want to run (sh "pwd" to check

sb08:04:25

Bad file location case: different the error message (exit 2). I think, he need to config python3 (maybe alias setup problem) on Windows. Or simply try with `

"python file.py"
python --version (could helpful)

zackteo08:04:10

Right python might not even be on the path ... :thinking_face:

ūüĎć 3
sb08:04:02

@U01MHDJSC76 I found an answer: error 9009 ‚ÄúThe python.exe you are using isn‚Äôt a real Python executable. It‚Äôs just a link to Microsoft Store to download it from there.‚ÄĚ maybe true?

Sebastian Ohlsson15:04:28

I will take a look into this, thank you

ūüĎć 3
Sebastian Ohlsson09:04:04

So I finally got back to this. Turns out that I had to type "python.exe" and not just "python3". Rookie misstakes were made ūüôā As you mentioned python3 just takes me to the windows store. Maybe there are different installation ways. Its solved, thanks for all the help.

zackteo10:04:43

Nice :D glad you managed to get it working!

ūüĎŹ 3
zackteo08:04:11

Hello! How do I do something like

(take 100 (cycle [{:type :invoke, :f :write, :value (rand-int 5)}
                         (repeat 10 {:f :read})]))
But make the rand-int run again

raspasov08:04:31

(sequence
 (comp
  (take 100)
  (mapcat identity))
 (repeatedly
  (fn []
   [{:type :invoke, :f :write, :value (rand-int 5)}
    (repeat 10 {:f :read})])))

zackteo08:04:49

Right right! I should use a function and repeatedly

clojure-spin 3
zackteo08:04:49

Thanks ūüôā

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yuhan08:04:15

You could also use recursion~

((fn rec []
   (lazy-cat
     [{:type :invoke, :f :write, :value (rand-int 5)}
      (repeat 10 {:f :read})]
     (rec))))

raspasov08:04:18

As presented atm, the above is an infinite loop. Also, if you can solve your problem in straightforward way without recursion, you should.

yuhan08:04:23

yup, don't use recursion in normal circumstances - I think it's just an interesting thing for beginners to encounter

ūüĎć 3
raspasov08:04:55

Also, on the JVM direct recursion can blow up the stack, so be careful with recursion.

zackteo08:04:14

If I want to inc the value instead, would recursion be good for that then?

zackteo08:04:09

Like

(take 100 ((fn rec [x]
             (lazy-cat
               [{:type :invoke, :f :write, :value x}
                (repeat 10 {:f :read})]
               (rec (inc x)))) 0))

raspasov08:04:30

@UUSQHP535 Probably not:

(sequence
 (comp
  (take 100)
  (mapcat identity))
 (map
  (fn [n]
   [{:type :invoke, :f :write, :value n}
    (repeat 10 {:f :read})])
  (range)))

yuhan08:04:34

If each value depends on the previous ones, you can also look at iterate or reductions

zackteo08:04:57

right right :thinking_face:

raspasov09:04:36

(do
 ;bad - avoid
 #_(let [f-bad (fn inc-inc [x]
              (if (< 100000 x)
               x
               (inc-inc (inc x))))]
  (f-bad 0))

 ;OK to use
 (let [f-good (fn inc-inc [x]
                (if (< 100000 x)
                 x
                 #(inc-inc (inc x))))]
  (trampoline f-good 0)))

raspasov09:04:12

Notice that inc-inc returns a fn in the second case.

zackteo09:04:55

so the point is to use trampoline when doing recursion?

raspasov09:04:24

Yes… I believe in the example above, you might be able avoid the problem because the recursion is from within lazy-cat… But I am not 100% sure.

zackteo09:04:03

Will look into it ūüôā thanks

Stuart09:04:38

is their a way to do destructuring but give unique names to the keys, or should I just use a let? e..g

(defn is-left [{:keys [x y]} {:keys [x y]} {:keys [x y]}]
   ;; takes 3 parameters, all 3 have x and y key. BUt I'd like it to be like:
   ;; {px py} {x0 y0} {x1 y1}
)
Should I just do this?
(defn is-left [pxy xy0 xy1]
  (let [px (:x pxy)
        py (:y pxy)
        x0 (:x xy0)
        y0 (:y xy0)
     ... so on...]))

andy.fingerhut09:04:05

There is a way to do destructuring on maps, without using :keys, where you get to pick the local names for the value. See examples here: https://clojure.org/guides/destructuring#_associative_destructuring

andy.fingerhut09:04:29

:keys is unnecessary, but a nice shorthand when you want the local names to be the same as the keyword without the :

Stuart09:04:49

Thank you, that looks like that I want. TIL!

raspasov09:04:44

I recently wrote this REPL utility to solve this ‚Äúproblem‚ÄĚ ūüôā It will print the destructure form for you (for one map): https://github.com/raspasov/alexandria-clj/blob/main/src/ss/auto_let/core.cljc#L112

(ss.auto-let.core/de
 {:user/id    42
  :message/id 52
  :data       {:comment/id 62}})
[{:user/keys [id], message-id :message/id, :keys [data]} your-map {comment-id :comment/id} data]

raspasov09:04:04

(it’s not a library atm, but you can copy the namespace…)

raspasov09:04:59

It should do the ‚Äúright thing‚ÄĚ and avoid shadowing of locals for that map.

Milan Munzar11:04:25

Hello, do you guys have any tips on how to debug the 'pending puts errror' in core.async for ClojureScript? It happens after several days running on our server on nodejs platform. I understand what is happening, but have trouble identifying the code which is throwing the assertion. Thank you.

Dave Suico14:04:14

Hello guys, I'm trying to make a move file function that is done by copying the file to the new destination and removing the source after copying. However, I get a strange behavior since the io/delete-file function says "Couldn't delete" error so I'm checking the file manually and tried to rename it and it says it's locked since another program is using the file. Is the io/copy function not being able to release the lock to cause this such state? What should I do if so?

dpsutton14:04:02

(let [input (io/file "foo")]
    (println "contents: " (slurp "foo"))
    (io/copy input (io/file "bar"))
    (io/delete-file input)
    (println "contents: " (slurp "bar")))

dpsutton14:04:24

returns

contents:  hello

contents:  hello
and deletes foo after copying to bar

delaguardo14:04:27

io/copy doesn’t close any streams have a look at this example - https://clojuredocs.org/clojure.java.io/copy#example-5e008f1ce4b0ca44402ef7fe

dpsutton14:04:44

i suspect that you are holding two references to the file which is what your problem is

dpsutton14:04:20

notice i io/copy and then io/delte the same io/file. you make an io/file for the copy, and then make another one for the deletion

delaguardo14:04:30

and btw, consider using let instead of def withing defn. The difference that def creates global var and let is for making localy scoped references.

Dave Suico14:04:17

@U11BV7MTK am I having a race condition? I can't think of any ways to copy and delete the source file the clojure way

Dave Suico14:04:35

@U04V4KLKC I stand corrected, thank you!

delaguardo14:04:00

(defn move-file [source destination]
  (with-open [in (io/input-stream source)
              out (io/output-stream destination)]
    (io/copy in out))
  (io/delete-file source))

(spit "/tmp/foo" "lalala")              ; => nil

(slurp "/tmp/foo")                      ; => "lalala"

(move-file "/tmp/foo" "/tmp/bar")       ; => true

(slurp "/tmp/foo")                      ; throws FileNotFoundException

(slurp "/tmp/bar")                      ; => "lalala"

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dpsutton14:04:02

i don't think its a race condition. io/copy loops until it is done. i'd guess you're doing other stuff to the file

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Dave Suico15:04:33

@U04V4KLKC I'm still having the issue, the program using the file is OpenJDK Platform binary. I'm using Calva + VSCode how come OpenJDK be using this file?

dpsutton15:04:52

openjdk is the jvm. clojure runs on the jvm. openjdk is the vm that executes clojure code.

Dave Suico15:04:13

@U11BV7MTK I have followed @U04V4KLKC’s implementation but still no luck :(

dpsutton15:04:52

can you restart your repl and only execute this code? i'm guessing you've got some open file handlers to it somewhere

Dave Suico15:04:54

nah still the same.. here's what I did: -killed the current repl -started new repl via Calva jack-in -loaded the file and its dependencies -called the function

dpsutton15:04:09

can you evaluate *e at the repl? I wonder if the stacktrace has more information

dpsutton15:04:27

seeing that its on the desktop i'm wondering if permissions might come in to play here

Dave Suico15:04:08

:cause "Couldn't delete C:\\Users\\Dave Suico\\Desktop\\desktopCSV3.csv"  :via  [{:type http://java.io.IOException    :message "Couldn't delete C:\\Users\\Dave Suico\\Desktop\\desktopCSV3.csv"    :at [http://clojure.java.io$delete_file invokeStatic "io.clj" 434]}]  :trace  [[http://clojure.java.io$delete_file invokeStatic "io.clj" 434]   [http://clojure.java.io$delete_file doInvoke "io.clj" 430]   [clojure.lang.RestFn invoke "RestFn.java" 410]   [gmaven.csv.main$move_csv_file invokeStatic "main.clj" 43]   [gmaven.csv.main$move_csv_file invoke "main.clj" 36]   [gmaven.csv.main$read_and_move_csv invokeStatic "main.clj" 51]   [gmaven.csv.main$read_and_move_csv invoke "main.clj" 49]   [gmaven.csv.main$eval8153 invokeStatic "NO_SOURCE_FILE" 27]   [gmaven.csv.main$eval8153 invoke "NO_SOURCE_FILE" 27]   [clojure.lang.Compiler eval "Compiler.java" 7177]   [clojure.lang.Compiler eval "Compiler.java" 7132]   [clojure.core$eval invokeStatic "core.clj" 3214]   [clojure.core$eval invoke "core.clj" 3210]   [nrepl.middleware.interruptible_eval$evaluate$fn__960$fn__961 invoke "interruptible_eval.clj" 87]   [clojure.lang.AFn applyToHelper "AFn.java" 152]   [clojure.lang.AFn applyTo "AFn.java" 144]   [clojure.core$apply invokeStatic "core.clj" 665]   [clojure.core$with_bindings_STAR_ invokeStatic "core.clj" 1973]   [clojure.core$with_bindings_STAR_ doInvoke "core.clj" 1973]   [clojure.lang.RestFn invoke "RestFn.java" 425]   [nrepl.middleware.interruptible_eval$evaluate$fn__960 invoke "interruptible_eval.clj" 87]   [clojure.main$repl$read_eval_print__9086$fn__9089 invoke "main.clj" 437]   [clojure.main$repl$read_eval_print__9086 invoke "main.clj" 437]   [clojure.main$repl$fn__9095 invoke "main.clj" 458]   [clojure.main$repl invokeStatic "main.clj" 458]   [clojure.main$repl doInvoke "main.clj" 368]   [clojure.lang.RestFn invoke "RestFn.java" 1523]   [nrepl.middleware.interruptible_eval$evaluate invokeStatic "interruptible_eval.clj" 84]   [nrepl.middleware.interruptible_eval$evaluate invoke "interruptible_eval.clj" 56]   [nrepl.middleware.interruptible_eval$interruptible_eval$fn__991$fn__995 invoke "interruptible_eval.clj" 152]   [clojure.lang.AFn run "AFn.java" 22]   [nrepl.middleware.session$session_exec$main_loop__1058$fn__1062 invoke "session.clj" 202]   [nrepl.middleware.session$session_exec$main_loop__1058 invoke "session.clj" 201]   [clojure.lang.AFn run "AFn.java" 22]   [java.lang.Thread run "Thread.java" 832]]}

Dave Suico15:04:58

will check if I could run this in other drive

Dave Suico16:04:12

oh my apologies, this function actually works

dpsutton16:04:30

was it just lacking permissions to delete files from the desktop?

Dave Suico16:04:45

@U11BV7MTK actually the move-csv-file works by itself when called alone but now when I call read-and-move-csv the error happens. Your suspicion of 2 handles was right.

dpsutton16:04:22

don't use def like that. use let

Dave Suico16:04:38

yes yes, I'm still refactoring things

dpsutton16:04:01

no worries. it's possible that that's preventing garbage collecting since it's still defined and that prevents deletion

Dave Suico16:04:38

done refactoring with let, still the error persist when -reading csv to a variable -moving the csv to another path should I be wrapping these using with-open?

dpsutton16:04:15

can you post the source of move-csv-file as it currently is?

dpsutton16:04:51

and i'd restart your repl since you probably still have some defs around

Dave Suico16:04:01

Alright, I'm posting 2 functions

Dave Suico16:04:40

no more defs and I'm restarting my reply every time I call it

dpsutton16:04:05

oh where did the input streams come from? if you use (io/file source-file) you don't need to worry about the inputstreams

Dave Suico16:04:16

I just copied @U04V4KLKC’s snippet silly me

dpsutton16:04:11

no worries. the docstring of io/copy says it doesn't close any streams that it didn't open itself. If you provide the file, it will do the stream opening and closing so you don't need to worry about it

Dave Suico16:04:24

so in my case, my csv reader isn't closing my stream?

dpsutton16:04:36

can you restart your repl and post the source of these two functions again?

dpsutton16:04:50

and make sure no code is running at startup, no top level forms do work, etc

Dave Suico16:04:18

nevermind the defs, i'll refactor as we speak

Dave Suico16:04:25

I've refactored move-csv-file to this and it is working. Now to test read-and-move-csv

Dave Suico16:04:31

read-and-move-csv doesn't work

dpsutton16:04:14

ok. so that means one of the two branches csv-to-vector or read-csv must be interacting in a way to prevent it. do you know which branch is taken?

Dave Suico16:04:59

the read-csv function is doing the file reading, the csv-to-vector is only for converting the rows from read-csv if the user opts to

dpsutton16:04:20

and which branch is being taken?

Dave Suico16:04:46

uhm a library called ultra csv does the actual reading

dpsutton16:04:57

(if (true? as-vector?) (csv-to-vector source-file) (read-csv source-file)) only one of these two branches is taken. which branch is being taken?

Dave Suico16:04:27

my apologies I may have misled you, allow me to correct. both csv-to-vector and read-csv reference to the same library (ultra-csv)

dpsutton16:04:14

when you are calling the function read-and-move-csv you are passing in as-vector?. this influences the expression (if (true? as-vector?) (csv-to-vector source-file) (read-csv source-file)) . this form has two branches. which branch is being taken?

Dave Suico17:04:35

the as-vector parameter is a boolean variable. It depends on the client what value to assign in that variable when true, it will take you to csv-to-vector when false, just plain read-csv

dpsutton17:04:21

i completely understand that

dpsutton17:04:47

when you are invoking this function and saying that it doesn't work, what value are you passing in for as-vector? and therefore which branch is being taken?

Dave Suico17:04:11

uhm both false and true and both fails

dpsutton17:04:35

ok. well let's just stay with false and diagnose how read-csv will interact with deleting the file

dpsutton17:04:08

so we know that we are trying to delete the file after reading it. can you post the docstring for csv-reader/read-csv?

Dave Suico17:04:25

my bad, I should've known this earlier. I am rereading my tasks spec and I just realized that read-csv and move-csv are separate functions and they shouldn't be interacting with each other meaning read-and-move-csv shouldn't exist. .

Dave Suico17:04:32

read-csv and move-csv works when called alone I guess I'm just creating my own problem by putting them together as read-and-move-csv.ūüėÖ

dpsutton17:04:57

these tests show that there's a close! function that needs to be called. You'll need to ensure that you get all the data from the csv and then close it before trying to delete it. I suspect that's your problem there

‚̧ԳŹ 2
dpsutton17:04:13

this seems like a strange api to me

Dave Suico17:04:31

ahh now it's clear to me, that csv reader is not actually closing the file. Gotta add this closing call to my reader as well. I guess we'll end here thank you very much man I appreciate your efforts!

dpsutton17:04:50

i suspect you're going to have to figure out how to get all of the results out of the csv. it's possible it's lazy and gives you results as you need? not sure

Dave Suico17:04:52

yes it gives me the results I need but I have no idea yet how will it behave when dealing with large files or when the next call is move-csv

Dave Suico17:04:25

can you recommend other library for reading csvs?

dpsutton17:04:22

Clojure data csv is the go to

Dave Suico17:04:14

okay man I'm gonna try that

Eric Ihli14:04:34

I get a lot of help from this channel and just wanted to give a big thank you and show what your help has led to. I just released my first package on Clojars: https://clojars.org/com.owoga/tightly-packed-trie It's an implementation of a https://www.aclweb.org/anthology/W09-1505.pdf and helped me reduce the memory footprint of a language model from several gigabytes to several megabytes (a savings of $15 per month since I can use a $5/mo server rather than a $20/mo server; not a great return on time spent to be fair, but it was fun!). Sending encouragement to those of you new to Clojure and a big shout out to everyone in this channel providing so much help. Special thanks to @seancorfield for https://github.com/seancorfield/depstar and @andy.fingerhut for https://github.com/jafingerhut/cljol.

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2
andy.fingerhut14:04:19

There is no requirement to do so, but you are certainly welcome to announce your library in the #announcements channel on this Slack if you wish.

ūüôŹ 2
Andy Nortrup19:04:20

Testing question - I’m trying to test that a method outputs the proper date string.

(t/deftest test-print-period-date
           (t/is (= "2021-W53" (c/print-period-date c/period-week -1 (ti/date-time 2021 01 8))))
           (t/is (= "2020-12" (c/print-period-date c/period-month -1 (ti/date-time 2021 01 8)))))
The test is failing with this output:
; expected:
2021-W53
; actual:
(2020-W53)
The content is formatted properly, but I don’t appear to be doing the comparison / conversion correctly?

dpsutton19:04:29

what does (c/print-period-date c/period-month -1 (ti/date-time 2021 01 8)) output in your repl?

dpsutton19:04:09

also, i'm seeing an expectation of 2020 as the year but (ti/date-time 2021 ...) if that's your issue?

Andy Nortrup19:04:10

this was it. Thank you for helping me look at my own code and explain it. I should learn to type.

Andy Nortrup19:04:02

I get a quoted string back when I run it in REPL

dpsutton19:04:37

can you paste the output here?

Andy Nortrup19:04:18

(print-period-date period-week -1 (t/date-time 2021 01 8))
"2020-W53"

Andy Nortrup19:04:41

(package changes between my test and core NS)

dpsutton19:04:36

well that's certainly not equal to "2021-W53" which you were expecting

dpsutton19:04:54

it seems like your repl has some formatting of test results going on

dpsutton19:04:25

this is what it looks like for me for (is (= "bob" "alice"))

FAIL in (foo) (NO_SOURCE_FILE:1)
expected: (= "bob" "alice")
  actual: (not (= "bob" "alice"))
nil

Andy Nortrup19:04:10

this was it. Thank you for helping me look at my own code and explain it. I should learn to type.

yiorgos21:04:55

In Clojure, when I want to check the type of the data I normally do (class foo) but in Clojurescript that is not working, is there something similar in Clojurescript for examine the data, for example if it is a vector, map …

noisesmith00:04:52

the type function works in clj and cljs

ūüĎć 3
Lukas21:04:36

Hi there, can anyone tell me why this

(defmacro no-matching-ctor [q]
  (when (symbol? q)
    [(constantly true)]))

(no-matching-ctor ?e)
will give me an IllegalArgumentException
1. Caused by java.lang.IllegalArgumentException
   No matching ctor found for class clojure.core$constantly$fn__5690 
macroexpand returns what I expect, but it seems I expected some not working thing ūüė¨
(macroexpand '(no-matching-ctor ?e)) 
=> [#function[clojure.core/constantly/fn--5690]]

hiredman21:04:54

because you are returning a function object from the macro instead of code that evaluates to the function object

‚̧ԳŹ 3
hiredman21:04:05

basically https://clojure.atlassian.net/browse/CLJ-1206 but with a slightly different error message

omendozar22:04:17

Hi, how can I solve this using next.jdbc.sql/insert-multi! with postgres?

Can't infer the SQL type to use for an instance of java.util.Date. Use
   setObject() with an explicit Types value to specify the type to use.
This is my table:
create table in_sms  (
  in_sms_id serial not null primary key,
  codigo int not null,
  remitente text not null,
  mensaje text not null,
  fechaingreso timestamp without time zone not null,
  unique(codigo)
);
This is the input:
(def input [{:codigo 493
               :remitente "50588997766"
               :mensaje "Loren Ipsum"
               :fechaingreso #inst "2021-04-13T18:32:00"}
              {:codigo 494
               :remitente "50589890909"
               :mensaje "Loren Ipsum"
               :fechaingreso #inst "2021-04-13T18:33:00"}])
and this is my insert:
(defn insert-incoming-sms!
  "Insert multiple SMS."
  [db sms-coll]
  (let [values (->> sms-coll
                   (mapv vals)
                   (map vec)
                   vec)]
    (sql/insert-multi! db :in_sms
                       [:codigo :remitente :mensaje
                        :fechaingreso]
                       values)))

seancorfield23:04:18

@orlandomr27 The next.jdbc documentation talks about this… just a sec, let me pull up the link…

seancorfield23:04:12

https://cljdoc.org/d/com.github.seancorfield/next.jdbc/1.1.646/doc/getting-started#working-with-additional-data-types ‚ÄĒ ‚ÄúIn particular, PostgreSQL does not seem to perform a conversion from java.util.Date to a SQL data type automatically. You can require the next.jdbc.date-time namespace to enable that conversion.‚ÄĚ

2
clojure-spin 2
omendozar23:04:05

worked like a charm!

2
seancorfield23:04:15

There‚Äôs a lot of documentation for next.jdbc so it can seem a bit overwhelming, but I would recommend reading through the entire thing at least once ‚ÄĒ and since you are using PostgreSQL, there‚Äôs a whole section in the Tips &amp; Tricks page that will help you with various custom PG types.

seancorfield23:04:17

There‚Äôs a #sql channel where it can be easier to get help on JDBC/SQL stuff (since it‚Äôs much lower traffic than #beginners ‚ÄĒ and I have #beginners muted so I don‚Äôt always see next.jdbc questions here, but I don‚Äôt have #sql muted ūüôā ).

omendozar23:04:16

I‚Äôm reading and consulting the docs while composing my functions, but somehow I missed this part. Thank you @seancorfield I‚Äôm gonna post further questions on #sql channel. By the way! Awesome work with next.jdbc ūüôā

seancorfield23:04:28

Also, be very careful about (mapv vals) over a sequence of hash maps ‚ÄĒ hash maps are unordered so you will not necessarily get the columns in the order you expect (and you aren‚Äôt really guarantee each hash map will return keys in the same order).

seancorfield23:04:46

The safest thing to do there is (mapv (juxt :codigo :remitente :mensaje :fechaingreso) sms-coll) so you can control the order of the columns.

omendozar23:04:42

ūüė≤ I wasn‚Äôt aware of that. Thanks!

seancorfield23:04:51

To avoid repetition, you could do:

(let [cols [:codigo :remitente :mensaje :fechaingreso]]
  (sql/insert-multi! db :in_sms cols (mapv (apply juxt cols) sms-coll)))

2