I’m working on this one right now, http://www.4clojure.com/problem/22

Crazy how hard it is to figure out how to solve in Clojure

The "special restrictions" is amusing, because that would otherwise be the one-word answer.

exactly!

Basically means you need to write the count function. I would use loop/recur.

I hate loop/recur.

reduce also works.

What's wrong with loop/recur?

It always feels awkward. I prefer into or for instead. Or a custom transducer for some things.

Can’t even follow what you guys are talking about lol

Josh, just put all those words on separate pieces of paper, shuffle them, and choose one. Look up the page and it will help to solve the problem.

Is clojuredocs working again?

Just look at the info on into and for and you'll see what they can do.

My favorite clojure function, now with transducer support:

"into" makes a collection. Need to turn collection into scalar here.

https://clojuredocs.org/clojure.core/into

"reduce" will be much easier.

https://clojuredocs.org/clojure.core/reduce

I'll take into with transducers over reduce 99 times out of 100.

But I haven't looked at the problem you're trying to solve.

Josh, do you have access to REPL to try out partial solutions? That exercise page looks a little unforgiving if you can't test out your solutions.

Yes, always work in a REPL.

Cursive makes this super easy. (Once you get the darn thing configured.)

Josh, I'll help you through a reduce-based solution. Need to hear that you're ready though. 😉

@joshua.d.horwitz: Are you still there?

@ericlavigne: His profile status would appear to indicate otherwise.

Hello.

Need help)

I have a lein-project. Here is its structure

.
├── CHANGELOG.md
├── doc
│   └── intro.md
├── LICENSE
├── project.clj
├── README.md
├── resources
├── src
│   └── clojure_sicp
│       ├── braveclojure
│       │   └── brave.clj
│       └── core.clj
├── target
│   ├── base+system+user+dev
│   │   ├── classes
│   │   │   └── META-INF
│   │   │       └── maven
│   │   │           └── clojure-sicp
│   │   │               └── clojure-sicp
│   │   │                   └── pom.properties
│   │   ├── repl-port
│   │   └── stale
│   │       └── leiningen.core.classpath.extract-native-dependencies
│   └── base+system+user+dev+test+test
│       ├── classes
│       │   └── META-INF
│       │       └── maven
│       │           └── clojure-sicp
│       │               └── clojure-sicp
│       │                   └── pom.properties
│       └── stale
│           └── leiningen.core.classpath.extract-native-dependencies
└── test
    └── clojure_sicp
        └── core_test.clj

Q: How to run file brave.clj?

I've tried lein run -m clojure-sicp.braveclojure.brave

Here is brave.clj

(ns clojure-sicp.braveclojure.brave)

(defn latlng->point
  "Convert lat/lng map to comma-separated string"
  [latlng]
  (str (:lat latlng) "," (:lng latlng)))

(defn points
  [locations]
  (clojure.string/join " " (map latlng->point locations)))

(def heists [{:location "Cologne, Germany"
              :cheese-name "Archbishop Hildebold's Cheese Pretzel"
              :lat 50.95
              :lng 6.97}
             {:location "Zurich, Switzerland"
              :cheese-name "The Standard Emmental"
              :lat 47.37
              :lng 8.55}
             {:location "Marseille, France"
              :cheese-name "Le Fromage de Cosquer"
              :lat 43.30
              :lng 5.37}
             {:location "Zurich, Switzerland"
              :cheese-name "The Lesser Emmental"
              :lat 47.37
              :lng 8.55}
             {:location "Vatican City"
              :cheese-name "The Cheese of Turin"
              :lat 41.90
              :lng 12.45}])

(println (points heists)) 

Here output

lein run clojure-sicp.braveclojure.brave
50.95,6.97 47.37,8.55 43.3,5.37 47.37,8.55 41.9,12.45
Exception in thread "main" java.lang.IllegalStateException: heists already refers to: #'clojure-sicp.braveclojure.brave/heists in namespace: clojure-sicp.core, compiling:(clojure_sicp/core.clj:7:1)
        at clojure.lang.Compiler.analyzeSeq(Compiler.java:6875)
        at clojure.lang.Compiler.analyze(Compiler.java:6669)
        at clojure.lang.Compiler.analyze(Compiler.java:6625)
        at clojure.lang.Compiler.eval(Compiler.java:6931)
        at clojure.lang.Compiler.load(Compiler.java:7379)
        at clojure.lang.RT.loadResourceScript(RT.java:372)
        at clojure.lang.RT.loadResourceScript(RT.java:363)
        at clojure.lang.RT.load(RT.java:453)
        at clojure.lang.RT.load(RT.java:419)
        at clojure.core$load$fn__5677.invoke(core.clj:5893)
        at clojure.core$load.invokeStatic(core.clj:5892)
        at clojure.core$load.doInvoke(core.clj:5876)
        at clojure.lang.RestFn.invoke(RestFn.java:408)
        at clojure.core$load_one.invokeStatic(core.clj:5697)
        at clojure.core$load_one.invoke(core.clj:5692)
        at clojure.core$load_lib$fn__5626.invoke(core.clj:5737)
        at clojure.core$load_lib.invokeStatic(core.clj:5736)
        at clojure.core$load_lib.doInvoke(core.clj:5717)
        at clojure.lang.RestFn.applyTo(RestFn.java:142)
        at clojure.core$apply.invokeStatic(core.clj:648)
        at clojure.core$load_libs.invokeStatic(core.clj:5774)
        at clojure.core$load_libs.doInvoke(core.clj:5758)
        at clojure.lang.RestFn.applyTo(RestFn.java:137)
        at clojure.core$apply.invokeStatic(core.clj:648)
        at clojure.core$require.invokeStatic(core.clj:5796)
        at clojure.core$require.doInvoke(core.clj:5796)
        at clojure.lang.RestFn.invoke(RestFn.java:408)
        at user$eval5$fn__7.invoke(form-init8450613833812556873.clj:1)
        at user$eval5.invokeStatic(form-init8450613833812556873.clj:1)
        at user$eval5.invoke(form-init8450613833812556873.clj:1)
        at clojure.lang.Compiler.eval(Compiler.java:6927)
        at clojure.lang.Compiler.eval(Compiler.java:6917)
        at clojure.lang.Compiler.load(Compiler.java:7379)
        at clojure.lang.Compiler.loadFile(Compiler.java:7317)
        at clojure.main$load_script.invokeStatic(main.clj:275)
        at clojure.main$init_opt.invokeStatic(main.clj:277)
        at clojure.main$init_opt.invoke(main.clj:277)
        at clojure.main$initialize.invokeStatic(main.clj:308)
        at clojure.main$null_opt.invokeStatic(main.clj:342)
        at clojure.main$null_opt.invoke(main.clj:339)
        at clojure.main$main.invokeStatic(main.clj:421)
        at clojure.main$main.doInvoke(main.clj:384)
        at clojure.lang.RestFn.invoke(RestFn.java:421)
        at clojure.lang.Var.invoke(Var.java:383)
        at clojure.lang.AFn.applyToHelper(AFn.java:156)
        at clojure.lang.Var.applyTo(Var.java:700)
        at clojure.main.main(main.java:37)
Caused by: java.lang.IllegalStateException: heists already refers to: #'clojure-sicp.braveclojure.brave/heists in namespace: clojure-sicp.core
        at clojure.lang.Namespace.warnOrFailOnReplace(Namespace.java:88)
        at clojure.lang.Namespace.intern(Namespace.java:72)
        at clojure.lang.Compiler$DefExpr$Parser.parse(Compiler.java:546)
        at clojure.lang.Compiler.analyzeSeq(Compiler.java:6868)
        ... 46 more

Please explain.

When you call lein run -m NAMESPACE without explicit MAIN_FUNCTION leiningen lookup -main in NAMESPACE. If your NAMESPACE doesn't have one it run main function from namespace declared under :main option in project.clj file.

try read lein help run

i've read)

And obviously there is no need to call clojure as any script language)

I understand how to run core.clj, but didn't understand how to run any other file

just require any namespace into core.clj

(ns any.core
  (:require [any.foo :as foo]))

(defn -main [& args]
  (foo/bar))

like this

you should pay attention that there is no need to call "another file". operate with namespaces in your program

https://blog.8thlight.com/colin-jones/2010/12/05/clojure-libs-and-namespaces-require-use-import-and-ns.html

what is bar in foo/bar?

function in any.foo namespace

(defn -main
  [& args]
  (brave/(println (points heists)))

no

(defn -main [& args]
  (println (brave/points brave/heists)))

because (println (brave heists)) is not a function

its function call

In brave.clj

(defn print1
  (println (points heists)))

In core.clj

(ns clojure-sicp.core
  (:require [clojure-sicp.braveclojure.brave] :as brave))



(defn -main
  [& args]
  (brave/print1))

right, its better for understand what is going on

but again

lein run clojure-sicp.braveclojure.brave
Exception in thread "main" java.lang.IllegalArgumentException: Parameter declaration "println" should be a vector, compiling:(clojure_sicp/braveclojure/brave.clj:33:1)

(defn print1 []
  (println (points heists)))

forgot about []

and after that you can start with lein run without namespace

lein run                                /cygdrive/c/Users/a_s/clojure-sicp 1
Exception in thread "main" java.lang.ClassCastException: java.lang.Boolean cannot be cast to clojure.lang.Symbol, compiling:(clojure_sicp/core.clj:1:1)

(ns clojure-sicp.core
  (:require [clojure-sicp.braveclojure.brave] :as brave))

should be

(ns clojure-sicp.core
  (:require [clojure-sicp.braveclojure.brave :as brave]))

https://gist.github.com/ghoseb/287710/

it is.

ok. work.

it is quite difficult.

little practice and you will be happy with clojure)

This is the only way to run the examples from the book http://www.braveclojure.com/do-things/#Pulling_It_All_Together ? That is, write the code in one file, then in core.clj:

(ns clojure-sicp.core
  (:require [clojure-sicp.braveclojure.brave] :as brave))

[clojure-sicp.braveclojure.brave] :as brave => [clojure-sicp.braveclojure.brave :as brave]

ye

misprint. in my file

[clojure-sicp.braveclojure.brave :as brave]

))

it happens)

мне показалось?

most clojure program has one entry point

@meow @ericlavigne Sorry Guys! I have a 8 month pregnant wife who needed me last night so I got dragged away lol

Family comes first. Understood.

I appreciate it, it’s getting pretty crazy the closer we get!

I’m trying to differentiate between Reduce, Map and Apply

Should be able to get help here. Best wishes on your impending delivery.

Thanks!

Hah, @joshua.d.horwitz, your life is about to change in a way you cannot even imagine. The first few months are incredible and fleeting so memorize, document, and journal every day. You’ll appreciate it later.

@akiva: I’m freaking out!

@joshua.d.horwitz, this is probably better off in #C03RZGPG3 but I highly recommend reading https://happiestbaby.com/product/the-happiest-baby-book-paperback/ and http://www.amazon.com/Sleep-Lady®%C2%92s-Good-Night-Tight/dp/1593155581/ref=sr_1_1?s=books&ie=UTF8&qid=1455634800&sr=1-1&keywords=sleep+lady+good+night+sleep+tight.

@akiva: That is great! Thanks for the advice, I’m going to get both, need all the help I can get!

@joshua.d.horwitz: Listen to your intuition and especially your wife's intuition. And forget about sleep for the next 13 years at least 😉

@yogidevbear: lol

I think I’ll lose more sleep when my daughter turns 13. And buy a bouquet of shotguns.

different one for every day of the week?

Yep, and double-barrelled ones for the weekend.

might have better luck with bear traps 😛

Hahaha. And anti-personnel landmines. And a moat that even Leinigen’s ants can’t cross.

There we’re slightly back on topic.

lol

what is wrong with this?: (apply js/Date. [2011 4 3]) is it not possible to use apply with a js function, or is ist something else i am doing wrong?

hmmm, not sure. You might want to ask in #C03S1L9DN

I don’t know if js/Date. is a function

I’ve never had to do that, so haven’t run into a scenario like yours

@thomasdeutsch: It appears to be a JavaScript restriction. new and apply don’t seem to mix the way you’re expecting it to

http://stackoverflow.com/questions/1606797/use-of-apply-with-new-operator-is-this-possible

yeah, I don’t think new is a function

I would recommend using cljs-time for working with dates https://github.com/andrewmcveigh/cljs-time

if you are doing anything a little bit complicated.

i do not need that lib I did not know about this js restriction. thank you @solicode !