clojure

问题 I've been using emacs/slime for coding lisp, but with Clojure I found 'lein swank'. I must say that it's pretty useful, as I can connect to a server that runs clojure. How about the other Lisp implementations? What Lisp implementations provide the equivalent of 'lein swank' in Clojure? I mean, is there any other Lisp implementations that provide server connectivity so that I use 'M-x slime-connect', not just 'M-x slime'? 回答1: Non-clojure swank backends don't need a lein swank equivalent since

问题 Can one of the popular Java mocking frameworks like EasyMock or Mockito be used to mock Clojure protocols defined with defprotocol ? If so, how? 回答1: You should be able to mock protocols using any mock library. Under the covers, every protocol uses a Java interface as an implementation detail, and you could just mock that interface. That said, don't do this! Mocking in Java is absurdly complex because of reflection, protection levels, final classes, etc. Any time you want a Clojure object

问题 I want to add metadata to a byte array in Clojure. Since this is not allowed, one option I want to try is the simplest object wrapper that could work. Here is the source code for with-meta. That made me start looking at Clojure.lang.IObj . I haven't found what I want yet. 回答1: Here's how you can create a deftype that supports metadata. (import '(java.io Writer)) (deftype Box [value _meta] clojure.lang.IObj (meta [_] _meta) (withMeta [_ m] (Box. value m)) clojure.lang.IDeref (deref [_] value)

问题 For a class, I need to write some JVM code, and I'm hoping to use Clojure. I got it to work with the bottom part of the software stack, but I can't manage to make it work in between the GUI layer sitting on top and the bottom part. My main problem is getting the Java GUI to recognize my Clojure files. I want to use Leiningen for this, but the Java compiling solution doesn't seem to account for this interoperation. The answer here seems to be exactly what I need. I don't understand where to

问题 According to the ClojureDocs entry for line-seq (http://clojuredocs.org/clojure_core/clojure.core/line-seq) and the accepted answer for the Stack question (In Clojure 1.3, How to read and write a file), line-seq should return a lazy seq when passed a java.io.BufferedReader. However when I test this in the REPL, the type is listed as clojure.lang.Cons. See the code below: => (ns stack-question (:require [clojure.java.io :as io])) nil => (type (line-seq (io/reader "test-file.txt"))) clojure

问题 I wanna get the string representation of a variable. For example, (def my-var {}) How to get the string "my-var" from symbol my-var ? And (defn my-fun [] ...) How to get the string "my-fun" from function my-fun ? 回答1: user=> (def my-var {}) #'user/my-var user=> (defn my-fun [] ) #'user/my-fun user=> (name 'my-var) "my-var" user=> (name 'my-fun) "my-fun" user=> (doc name) ------------------------- clojure.core/name ([x]) Returns the name String of a string, symbol or keyword. nil 回答2: Every

问题 You can hint a return type in a protocol (defprotocol Individual (^Integer age [this])) and the compiler will make your methods comply: (defrecord person [] Individual (^String age [this] "one")) ; CompilerException java.lang.IllegalArgumentException: Mismatched return type: age, expected: java.lang.Object, had: java.lang.String, ... But you don't have to honour the type-hint: (defrecord person [] Individual (age [this] "one")) (age (new person)) ; "one" Does the type-hint have any effect?

问题 I'm trying to force SSL on my site. I want to have a ring style middle-ware to redirect the site to the same URL with https if it is only http I wrote the following code but it doesn't really do anything besides check the request scheme and print the URL it should be redirecting to. (defn https-url [request-url] (str (str (str (str "https://" (:server-name request-url) ":") (:server-port request-url))) (:uri request-url))) (defn require-https [handler] (fn [request] (let [page-request

问题 I have some code which works after replacing read-string with load-string. It is good that the code works, but I would like to know why. What is the difference between the two clojure functions? 回答1: Use load-string to sequentially read and evaluate the set of forms contained in the string Use read-string to read one object from the string s (both quoted from Clojure API) Load-string will evaluate your string as a Clojure expression, and read-string takes the string and returns it as the

问题 I'm very new in clojure. I want to print each item of list in newline. I'm trying like this: user=> (def my-list '(1 2 3 4 5 )) ;; #'user/my-list user=> my-list ;; (1 2 3 4 5) user=> (apply println my-list) ;; 1 2 3 4 5 ;; nil But I want my output must be: 1 2 3 4 5 nil can anyone tell me, How can I do this? Thanks. 回答1: This kind of use case (perform a side effect once for each member of a sequence) is the purpose of doseq. Using it here would be like (doseq [item my-list] (println item))