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Hello I'm getting a bit confused with js interop again may I ask what L.Polygon(latlngs).bindPopup('Hi There!').addTo(map); is equivalent to syntax wise ?
I would probably write something like:
(-> (L/Polygon latlngs)
(.bindPopup "Hi there")
(.addTo map))actually, cljs might require:
(-> L
(.Polygon latlngs)
(.bindPopup "Hi there")
(.addTo map))Okay let me try 🙂 I somehow always feel clojurescript interop is much tougher than java interop
Am doing react-leaflet and got what I wanted to do to work for now ...
[:> GeoJSON
;; [:> Popup "test"]
{:data sites
;; :color "#ffffff"
:onEachFeature (fn [feature layer]
(do (.bindPopup layer "test")
(js/console.log ;; (.. layer -feature -properties)
layer))
;; (.bindPopup (leaflet.) "hi")
)
:eventHandlers {:click #(js/console.log %)}}]But do you by any chance understand how this might be done?
function MyComponent() {
const map = useMap()
console.log('map center:', map.getCenter())
return null
}
function MyMapComponent() {
return (
<MapContainer center={[50.5, 30.5]} zoom={13}>
<MyComponent />
</MapContainer>
)
}[:> MapContainer
{:center [50.5 30.5] :zoom 13}]I’m guessing you probably mean to ask about children components (in this case, MyComponent) Something like this should work
[:> MapContainer
{:center [50.5 30.5] :zoom 13}
[:> MyComponent]
;; You can add as many children as you wish
]TBH - you may need to try some variations to get the right syntax, but this is essentially hiccup - multiple children, nested children - these typically work as you’d expect, save for some JS interop nuances.
Oh wait - I was under the impression you are looking to use some existing JS from CLJS. To clarify - is your question how you’d do everything in CLJS?
I think my questions is how does the syntax of <MyComponent> as well as its creation as a function get translated to cljs
Ok - your examples suggest you are already using reagent
MyComponent has no visual part to it. useMap doesn’t seem to refer to any pre-existing state. You may probably want to explain the purpose of MyComponent some more?
But do you by any chance understand how this might be done?
function MyComponent() {
const map = useMap()
console.log('map center:', map.getCenter())
return null
}
function MyMapComponent() {
return (
<MapContainer center={[50.5, 30.5]} zoom={13}>
<MyComponent />
</MapContainer>
)
}[:> MapContainer
{:center [50.5 30.5] :zoom 13}](->> (map #(+ 1 %) [1 2 3])
(map #(* 2 %))map keeps one-to-one correspondence, so a comp may be a good option to use
(->> [1 2 3] (map (comp #(* 2 %) #(+ 1 %))))I am a newbie developer. This might not be as clojure specific and more of a design question,: I want to separate my business logic and persistence logic into two namespaces. Currently its a mix. I have a namespace (lets call it ns1) that calls some upsert functions in another namespace (ns2). However, these functions in ns2 contain business logic, checks and validation and also upserts data into the database. This is a lot of responsibility of a single function, therefore i want to split them out. My idea was to create an additional namespace and basically have all data access happen in that. So ns1 will call ns2 which handles all the business logic and validation of the data and then calls ns3 which actually inserts, upserts, fetches the data. Does this sound like a solid idea? Another problem is the naming of these functions. Currently all functions in ns2 are named something like "upsert-placeholder-into-db" But when i remove the upsert functiontionality from ns2 into ns3, what would i call the ns2 function then? From the perspective of ns1 it would look weird that i call some "handle-placeholder" function when all i really want in n1 is to just insert the data. Maybe i am overthinking this. Sadly i cant' show you any of the code
Hi @U01GQRC8W30 — this is, as you suspected, not a strictly Clojure related question. May I ask what purpose the functions in ns-1 serve?
think of your names as fully qualified. it helps you to find good names.
Say you define a dbnamespace. then db/insert is a sufficiently descriptive name, so you just say (def insert …)
that would be a traditional name for code that handles validation, marshalling and buisness logic on top of data base records.
you can then say model/insert and db/insert! where the former is just a function and the latter does the actual transaction. But that is just an example to showcase how the namespace belongs to the name.
I’d recommend reading this article about Clojure web app frameworks: https://purelyfunctional.tv/mini-guide/what-web-framework-should-i-use-in-clojure/
not necessarily. there is a common design principle in clojure to avoid side effects and state. so ns2 would just be functions from data->data. ns3 would do the side effects.
Hello, I am using clojure.java.shell/sh to get my clojure backend to execute a python script and using :out (as in the print) to get the output. Previously, while perhaps not the most ideal option, this has worked for simpler outputs However, I currently have a script that prints out some initialisation and takes awhile - under a min to a few minutes to finish printing. This causes clojure.java.shell/sh to return before my script has completed. Is there a way to approach this?
ProcessBuilder is easy to use, it returns an outputstream or outputs to a file instead of giving you a string directly though
something like: (-> (ProcessBuilder. ["python" "-flag" "myfile.py"]) (.start) (.waitFor)) gives basic execution
this version shouldn't be hard to adapt for python:
(let [pb (ProcessBuilder. ["lua"])
p (.start pb)
out (.getOutputStream p)
in (.getInputStream p)]
(spit out "print \"hello from lua\"\n")
(slurp in))(it also demonstrates sending real time input to the process, you could even interact while the process runs based on its output...)
Here’s what I’d guess - the stdout isn’t flushed on program end, which leaves some of the output hanging. Depending on what python function you are using to print, try ensuring stdout flush as the last step before end?
oh as in :exit is 1. And realised my script was encountering errors and hence was returning ... let me fix my script first
how does [3 :a :c] translate to [:a :c :a :c :a] i would understand i think if there was another :c at the end. and you want the arguments repeated 3 times
(apply concat (take %1 (cycle %&))) I think
oh yeah, the lack of :c at the end makes this one fail
(defn g [n & items]
(butlast (into [] cat (repeat n items))))(g 3 :a :b :c) etcHello, how do I read a vector of python dictionaries as string. Like [{'a': 'test' , 'b': 'test}, {'b' : 'test'}, {'c' : 'test'}] in clojure?
Convert Python dictionaries that you have as string to a vector of Clojure hashmaps? Is my understanding correct?
You'll have to roll your own parser or use something like https://github.com/Engelberg/instaparse
There is also https://github.com/clj-python/libpython-clj if you want to do the conversion of data structures residing in memory rather than reading from a file
Or convert to an intermediary format (a conversion that you trust) like JSON and read that into Clojure
I formatted it to edn and used edn/read-string just need to do some key to keyword conversion i guess
Oh I thought you would be reading a lot of these, didn't know it was a one-off use case 😅
It is a fixed python script I am running and processing into my clojure backend i guess
(#(re-seq #".md" %) "what.md")My naive pseudo-code implementation would be this, but it doesn’t work
(#(re-seq (not #".md") %) "what.md")(first (str/split "what.md" #"\.md"))How do I get the parts that aren’t .md?
@U02108ERRU5 Like this you mean?
dev=> (second (re-find #"(.*)\.md" "what.md"))
"what"Awesome, thank you!
@U02108ERRU5 are you using the REPL?
@U050ECB92I am using the REPL. Why do you bring it up?
(def test ["what.md" "test.md" "sup.md"])
(map second (map re-find #"(.*)\.md" test))(map second (map #(re-find #"(.*)\.md" %) test))
Okay that works for the list… so @U04V70XH6, what am I missing? Why does that work and what I did at first not work?
take a string that you are saying it's not working on and try it in the repl. (re-find #(.*)\.md "some-string.markdown") or whatever and see what it returns
Because (map re-find #"(.*)\.md" test) is calling map with three arguments as if it were (map func coll1 coll2)
Which is not the same as (map #(func coll1 %) coll2)
Try (map vector [1 2 3] [4 5 6]) and (map #(vector [1 2 3] %) [4 5 6]) and you'll see the difference.
Ohhhh okay that makes sense, thank you for the explanation
If I have some namespace A, that provides some function f, and I want to make a new namespace B that provides the same function, what would the best way to go about it be?
You'll lose metadata on f doing that. I guess the question is: why do you want to do this?
(re-exporting vars from nses is a bit of a code smell, IMO)
The short answer is because I have to. The longer answer is because in this case, module B isn't actually written in clojure(script), but happens to satisfy the namespace protocol.
But because I want the effect of the code analyzer, I want to reprovide it from another module that is written in clojurescript.
If I have to, I can also write full blown wrapper functions to reify error checking done by B/f
As long as you don't care about metadata, (def f A/f) is probably sufficient. If you do care, you'll need something fancier that copies across the metadata into the B ns... but I'm not sure what that would look like in ClojureScript.
Eh, okay, thanks. Since B is sort of side-loaded into my environment there isn't any metadata (so it has to be provided by A anyway), so thanks. 🙂
(defn find-name-in-name [name1 name2]
(re-seq (re-pattern name1) name2)) ; okay so this works
(find-name-in-name "GIF" "animated GIF for GuidedTrack")I figured it out!
(defn find-name-in-name-experiment [name1 name2]
(if (not (nil? (re-find (re-pattern name1) name2)))
name2
nil))(and (re-find (re-pattern name1) name2) name2)
Or (when (re-find (re-pattern name1) name2) name2) if you prefer.
(if (not (nil? x)) y z) is just (if x y z) BTW
(except when x is false -- but in this case they'd be the same)
@wme.weeks Can you elaborate? I'm not quite sure what you're asking...
Do you mean "How can I install Clojure so I can use it from the Powershell command-line?" -- if so, try https://github.com/clojure/tools.deps.alpha/wiki/clj-on-Windows
Or is this a java shell interop question?