I don't think this problem is supposed to be solved like that right 😄

https://i.imgur.com/w5DsMBd.png

haha

Or this? 🙂

#((apply vector %1) %2)

very good 😄

#((vec %1) %2)

vec/vector .. confusing

I was already wondering why (vector) didn't work on its own

yea idk, probably legacy

vec converts another collection into a vector, vector creates a vector with the arguments as elements, e.g

user=> (vec #{1 2 3})
[1 3 2]
user=> (vector #{1 2 3})
[#{1 3 2}]

Can some one tell me the difference of the below (let [ k "rain"] (println (str "It is going to " k))) It is going to rain nil (let [ k "rain"] (str "It is going to " k)) It is going to rain Why are we using the println when str does the same?

Is there anyway I can 'inject' a variable in a cljs file during build time? using lein cljsbuild auto?

@mario.cordova.862 See the :closure-defines compiler option

@mfikes Thanks! I am using :closure-defines but its not replacing the default value for some reason. Still poking around though

How do you define :closure-defines if you have a ns set up as (ns myproj.api . . .)?

:closure-defines {"myproj.api/myvariable" "test"}?

:closure-defines {'myproj.api/myvariable "test"}?

:closure-defines {myproj.api/myvariable "test"}?

Non work BTW

so, when we are writing Clojure code, you're literally writing lists and nested lists? and it happens that, for your "code", i mean, list haha, be evaluated, clojure reader expects your first item to be a function, a macro or a special operator, else an exception is thrown. Is that correct?

That’s a pretty good summary, of course it’s not only lists but also vectors, maps etc but that’s the general gist.

As in, to write a defn you have to also type a vector for the arguments, right?

yes! wow Clojure is awesome haha

user> (class '(+ 1 1))
clojure.lang.PersistentList

Which turns out, that a List is just a directly implementation of lSeq

user> (seq? (cons + (cons 1 (cons 1 '())))) 
true
user> (eval (cons + (cons 1 (cons 1 '()))))
2

my mind is going to explode

one small gotcha here: the list? function isn't actually something you should use (it returns false for most seqs, and for cons for example)

yeah, i noticed that, when i have to check if it's a list, i prefer to use seq?

If anyone was curious >For :optimizations :none, a :main option must be specified for defines to work, and only goog-define defines are affected. :closure-defines currently does not have any effect with :optimizations :whitespace.

Which is why my :closure-defines were not taking effect.

I'm struggling to convert a java sample to clojure as I don't know java. Anyways, i'm trying to convert the below sample

SharedKeyCredentials creds = new SharedKeyCredentials(accountName, accountKey);
final ServiceURL serviceURL = new ServiceURL(new URL("http://" + accountName + "."), StorageURL.createPipeline(creds, new PipelineOptions()));
containerURL = serviceURL.createContainerURL("quickstart");

(defn blob-client []
  (let [s-url (ServiceURL. (java.net.URI. "") (StorageURL/createPipeline (storage-creds) (PipelineOptions.)))]
    ((.createContainerURL s-url)))

for starters, I'd turn every definition in the java into a let binding

(let [creds ... service-url ...] ...)

((...)) in an interop form is pretty much always an error

you should be able to have a translation where each line of java becomes one line of clojure

I'm specifically confused about how to create this serviceURL.createContainerURL("quickstart"); I have a service-url let binding but I can't seem to figure out how to call a method on a bound variable

(.createContainerURL service-url “quickstart”)

going through "the joy of clojure" and looking at the section that describes having tests in meta data the get ran by clojure.test/run-tests.. Is there a rule on a time and place to use this functionality, or is it best to keep tests in a test directory?

I've never seen a project that actually uses that feature

I have yet to come across one myself..

but admit to having tunnel vision on the code bases I have looked through

@alexmiller Thanks!

Am I able to extend-type of vectors so I can add them e.g. (+ [2 2] [4 4])?

Thus that would do a component-wise addition of the two vectors? Or is that the wrong thinking and I'm better off making a function? Cheers

the problem is that + isn't defined in a way that allows such extension

you could make your own plus multimethod, that uses + for numbers, and your own code for data structures

You can even name your fn +

that's also true, but more tedious to use from other code

Making its fully qualified name clojure.core/+ would involve unpleasant and fragile surgery that others could not consume easily. making its fully qualified name my.new.ops/+ is much easier.

Oh so you're saying extend + not vector or whatever it's type is?

Oh yeah I guess it needs to know how to deal with those operands, right?

right, clojure.core/+ isn't really extensible (IIRC making it extensible would be really bad for clojure performance)

so you'd be making a standin for it, that can be extended

or maybe you care about performance, then you'd likely be looking at one of the matrix libs instead of doing all this yourself...