在 emacs cider 中的 Clojure 中启动一个简单的程序并得到“没有这样的命名空间：你好”

Question

我尝试使用 emacs 运行一个类似于 clojure 'hello world' 的程序，但它给出了错误

No such namespace: hello

。

当我在终端中启动它时，效果很好：

u@h:~/hello-world$ clj -X hello/run
Hello world, the time is 07:52 am
u@h:~/hello-world$ 

但在带有苹果酒的 emacs 中则不然。

节目摘自网站：

https://clojure.org/guides/deps_and_cli#_writing_a_program

我展示了项目的树：

u@h:~/hello-world$ find |grep -v cache 
.
./.clj-kondo
./src
./src/hello.clj
./.lsp
./.nrepl-port
./deps.edn

内容：

./src/hello.clj

(ns hello
  (:require [java-time.api :as t]))

(defn time-str
  "Returns a string representation of a datetime in the local time zone."
  [instant]
  (t/format
    (t/with-zone (t/formatter "hh:mm a") (t/zone-id))
    instant))

(defn run [opts]
  (println "Hello world, the time is" (time-str (t/instant))))

./deps.edn

{:deps
 {clojure.java-time/clojure.java-time {:mvn/version "1.4.2"}}}

现在我如何处理 emacs：

CTRL + x CTRL + f ~/hello-world/src/hello.clj

CTRL + c CTRL + x j j

出现：

;; Connected to nREPL server - nrepl://localhost:34699
;; CIDER 1.15.1 (Cogne), nREPL 1.2.0
;; Clojure 1.11.4, Java 17.0.12
;;     Docs: (doc function-name)
;;           (find-doc part-of-name)
;;   Source: (source function-name)
;;  Javadoc: (javadoc java-object-or-class)
;;     Exit: <C-c C-q>
;;  Results: Stored in vars *1, *2, *3, an exception in *e;
;; ======================================================================
;; If you’re new to CIDER it is highly recommended to go through its
;; user manual first. Type <M-x cider-view-manual> to view it.
;; In case you’re seeing any warnings you should consult the manual’s
;; "Troubleshooting" section.
;;
;; Here are a few tips to get you started:
;;
;; * Press <C-h m> to see a list of the keybindings available (this
;;   will work in every Emacs buffer)
;; * Press <,> to quickly invoke some REPL command
;; * Press <C-c C-z> to switch between the REPL and a Clojure file
;; * Press <M-.> to jump to the source of something (e.g. a var, a
;;   Java method)
;; * Press <C-c C-d C-d> to view the documentation for something (e.g.
;;   a var, a Java method)
;; * Print CIDER’s refcard and keep it close to your keyboard.
;;
;; CIDER is super customizable - try <M-x customize-group cider> to
;; get a feel for this. If you’re thirsty for knowledge you should try
;; <M-x cider-drink-a-sip>.
;;
;; If you think you’ve encountered a bug (or have some suggestions for
;; improvements) use <M-x cider-report-bug> to report it.
;;
;; Above all else - don’t panic! In case of an emergency - procure
;; some (hard) cider and enjoy it responsibly!
;;
;; You can remove this message with the <M-x cider-repl-clear-help-banner> command.
;; You can disable it from appearing on start by setting
;; ‘cider-repl-display-help-banner’ to nil.
;; ======================================================================
;;  Startup: /usr/local/bin/clojure -A:dev -Sdeps \{\:deps\ \{nrepl/nrepl\ \{\:mvn/version\ \"1.2.0\"\}\ cider/cider-nrepl\ \{\:mvn/version\ \"0.49.1\"\}\}\ \:aliases\ \{\:cider/nrepl\ \{\:main-opts\ \[\"-m\"\ \"nrepl.cmdline\"\ \"--middleware\"\ \"\[cider.nrepl/cider-middleware\]\"\]\}\}\} -M:cider/nrepl
user>

然后我输入：

(hello/run)

并得到：

user> (hello/run)
Syntax error compiling at (*cider-repl ~/hello-world:localhost:34699(clj)*:43:7).
No such namespace: hello
user> 

我在 emacs 中做错了什么？

Answer 1

您必须首先需要命名空间才能使用它：

(require 'hello)

。

请注意，单段命名空间已被弃用，您可能会收到来自 IDE/REPL/linter/其他任何内容的投诉。您可以通过创建目录

src/hello

并将

src/hello.clj

移动到例如目录来修复它。

src/hello/main.clj

或

src/hello/core.clj

。当然，您必须使用

hello.main

或

hello.core

而不仅仅是

hello

，但您可以为命名空间添加别名：

(require '[hello.main :as hello])

。