Anybody knows what is the reasoning of using a def instead of atom for com.stuartsierra.component ? Am I missing something?

In what context @funyako.funyao156?

@mg Development context, most of the example I see use something like set-init! which just calls alter-var-root

@mg like this https://github.com/stuartsierra/component.repl/blob/master/src/com/stuartsierra/component/repl.clj

Because atom is for synchronized mutation and then you need a deref (or @) whereas this workflow does not need synchronization because the only change to the value is at startup of your app (and shutdown) -- and you don't need deref with a simple Var.

You certainly could store it in an atom and use swap! to start / stop the component, if you don't mind the additional deref to access the component.

But the intent implied by atom vs Var is different.

Does that help @funyako.funyao156?

@seancorfield Thank you for the explanation!

What's the biggest strength of transducers?

@lockdown- Probably that it combines all the functions steps together without creating intermediate sequence results from each step.

into with the transducing arity will impress your friends

@seancorfield so it's mostly about performance?

@lockdown- I'm not sure I'd it's "mostly" that, but that is certainly a big plus.

The decoupling of the transformations from the input and output types is also important.

For example, I can write a transducer and it can be applied to a collection, to a core.async channel, to a reducible-query... and the result can be fed into all sorts of different things.

Ok, gonna read up on them, was going to postpone them but they look like a nice abstraction

Also, they're simpler, in the hickeyian sense :)

@lockdown- To add, I think they have a nice way to do stateful computation

I have just started clojure does anyone uses VScode for clojure. If yes what plugin do you guys suggest me? Main feature i want to have is jumping to the functions definitions, please help. I have used Clojure plugin by Andrey Lisin, func jump is only working for the inbuild funcs like println, reduce the jump is not working for my defined functions, please help

does anyone have experience with lighttable?

i am just trying it out

cant run lein project

which i am working on in emacs

do i just enter project.clj namespace and ctrl++enter - that should start it?

@lepistane I thought Lighttable was abandonware

it kindof is

lighttable was abandoned in favor of eve which hasn't been released and totally won't be abandoned

I feel like work on eve already stopped too

eve has been abandoned https://groups.google.com/forum/#!topic/eve-talk/YFguOGkNrBo

Yeah that's the link I was looking for

Hi! I want to create a csv file without saving it on the disk (in order to return it to the client) i have noticed that write-csv can work with a writer instead of a file but i tried it with no success. Tried something like that:

(csv/write-csv (java.io.OutputStreamWriter. ) csv-data)

you can use a StringWriter

(let [b (java.io.StringWriter.)] (csv/write-csv b ["a" "b" "c"]) (.toString b))

This is random but does anyone know what is used to make these graphics? http://www.clara-rules.org/img/diagram/RULE.png

it looks similar to what http://bottlecaps.de/rr/ui generates

@hiredman Thanks. That helps.

In Luminus is there any equivalent to like bower or npm deps for third party assets?

@matt.raykowski there’s webjars for a lot of that

It works when you have the file in resources/public/... right?

yeah, you can do that too

But you're saying it'll work for ones I have not explicitly downloaded.

So I just need to go RTFM a bit about WebJars.

@matt.raykowski webjars is mechanism where people have packaged certain third party web things as maven artifacts, so you can put them in your project file like everything else. Then you need to add the middleware to serve them

the luminus docs introduce them here http://www.luminusweb.net/docs/assets.html

Okay cool. That's working for CSS.

What if I want to require a JS file in cljs? Is there a good example of that?

in my experience it worked to treat it just as I would css. The starting index page contains a tag that pulls the resource in, and the resource is in the jar via the resources directory so that the server can send it to the client

@noisesmith That approach will not work with CLJS advanced compilation

It will work with simple though, I believe

advanced compilation had nothing to do with requiring the resource, in my experience

we made externs files by hand

perhaps there's a newer easier way to do things, I would be ignorant of it though

from what I've seen, there are packages that give you js plus externs, and attempts to auto-generate externs. I can't vouch for any of them

I want to be able to call (do-in-seq (println "1") (println "2"))

You want a macro that works just like Clojure's built-in "do", as an exercise to understand how to do it? Or if you want something that behaves differently than built-in "do", how do you want its behavior to differ?

I want it to for sure execute sequentially for stateful change that have to happen in order.

have you ever seen how you would implement do using the lambda calculus?

Clojure's built-in "do" is sequential

eg execute sql to empty a table then fill it up