How do you display all dirs of classpath in clojure?
This is a common question that clojure CLI has covered now. See answer below.
in your projects' dir run:
clojure -Spath
Related
I am very new to both Clojure and Leiningen. I have installed Clojure on Windows at C:\clojure-1.5.1 and leiningen-win-installer beta1 at C:\.lein\bin.
Now I am trying the example from Eric Rochester's book. I have included dependent libraries for Incanter in project.clj and also using dep.
How do I use the command (use 'incanter.core)? I am getting 'use' is not recognized as an internal or external command. In addition, how do I use lein commands at user=>?
Edit - I forgot "lein deps" until I saw Mars's answer
Before you start lein repl, you have to make the project (with "lein new getting-data" or whatever is in the book).
That makes a new directory, and in that directory you find and edit "project.clj" to include the dependencies (as shown in book).
cd into the directory that project.clj is in and run "lein deps" from the dos/powershell prompt.
THEN when you run lein repl, from within that same directory, at the user=> prompt, do
(use 'incanter.core)
and it will come back with "nil" and you'll be running. You might want to first run some examples from the leiningen page to get more of a feel for lein. You always type clojure commands at the "user=>" prompt, not at the "c:....>" prompt.
There's a bit of subtlety in Leiningen project.clj's. I haven't found an easy introduction. Levin Magruder's advice will no doubt get you started. The basic idea is that once the project file is set up correctly, lein deps will go out and find the libraries you need, and put them in a place where lein repl can find them. Then use will work for the libraries that have been downloaded. For more info, study of the detailed comments project.clj sample file may be helpful. (Not part of the answer to this question, but if you're having problems with use, you're likely to get tripped up by ns and filenames soon (I was): I recommend Colin Jones' introduction to ns and its options.)
We want to automate the production of a Leiningen project tree
entirely from an org-mode babel file. We want to do this so that we
can also create beautiful, typeset documentation via
org-latex-export-to-pdf. We want no less than full literate
programming in Clojure from org-mode.
The following command:
$ lein new ex1
produces a tree that looks like this:
ex1
ex1/.gitignore
ex1/doc
ex1/doc/intro.md
ex1/project.clj
ex1/README.md
ex1/resources
ex1/src
ex1/src/ex1
ex1/src/ex1/core.clj
ex1/test
ex1/test/ex1
ex1/test/ex1/core_test.clj
We want to do the identical thing just by running
org-babel-tangle, and no more, in our org-mode buffer in
emacs.
A difficulty arises: whereas tangle is happy to produce
files in existing subdirectories like src and test, it seems reluctant to produce the subdirectories if they don't exist. That means we must
create the directory structure by some other means -- unless we can
get tangle to do it for us, and that's the subject of this
StackOverflow question.
There are six files in the directory structure created by Leiningen. I can remove them all and re-create them from my org-file with BEGIN_SRC blocks such as the following
#+BEGIN_SRC clojure :tangle ./ex1/src/ex1/core.clj
(ns ex1.core)
(defn foo
"I don't do a whole lot."
[x]
(println x "Hello, World!"))
#+END_SRC
Notice particularly the name of the subdirectory path
#+BEGIN_SRC clojure :tangle ./ex1/src/ex1/core.clj
All is well if our directory structure already exists. org-mode's tangle will
create or update all six files described above and create new files in any existing directory. We don't know how to
get tangle to produce the directories; it complains that there is no such
directory.
A copy of the desired .org file can be found here if you would like more details.
It is possible use the following header in the begin_src section,
:mkdirp yes
FYI There's now a lein project template for using org based projects:
https://github.com/thi-ng/thing-babel
I'm running into problems because the library I have appears to conflict with the published documentation. I had a few problems with getting the right version of things installed before, and I'm wondering if this is the cause.
Is there any way to print out which jars were loaded in the repl so I can check?
You can also use query lein for
the classpath with lein classpath
a dependency tree printout with lein deps :tree
This might also help:
lein deps :tree - shows a tree of dependencies that get pulled in
[library "version" :exclusions [some-other-lib "version"]] - exclude the some-other-lib that gets pulled in by some library.
You can then manually pull in the right version of some-other-lib by defining your own dependency vector.
(System/getProperty "java.class.path")
There are several options:
using java interrop: (System/getProperty "java.class.path"), (println (seq (.getURLs (java.lang.ClassLoader/getSystemClassLoader))))
clojure/java.classpath contains useful functions: like system-classpath
lein: lein classpath and lein deps :tree
boot: boot show -p, as well as useful function in boot environnement. Maybe have a look at martinklepsch/boot-deps.
For boot, I also wrote nha/boot-deps that helps managing dependency conflicts.
In Leiningen, is there something like Mavens "mvn help:effective-pom"?
I want to know which dependencies are imported as transitive deps of my deps.
Not sure if this is exactly what you're looking for, but with Lein 2 you can run lein deps :tree to see a dependency tree.
uvtc response is right, but remember that you can always do "lein pom" to generate a pom and then work with whatever maven tool/plugin you want
I was just looking for an answer to the same question when I saw this page. In the meanwhile, I have discovered
lein pprint
which does something very similar to help:effective-pom
I'm trying to set up a simple clojure project, and I'm not sure how to load files between the project. I'm sure that the answer is in the documentation, but I can't find a simple answer any where and I'm not sure where to look.
Essentially, my directory looks like this:
Clojure/
clojure/
clojure.jar
other clojure files
clojure-contrib/
clojure-contrib.jar
other contrib files
project/
main.clj
utils.clj
And I want main.clj to be something like this:
(ns project.main
(:require project.utils))
(greet)
and utils.clj to be something like this:
(ns project.utils)
(defn greet [] (println "Hello, World!"))
But that fails with:
Exception in thread "main" java.io.FileNotFoundException: Could not locate project/utils__init.class or project/utils.clj on classpath: (main.clj:1)
When I attempt to run it. My classpath includes the top Clojure/ directory and both jars. I also tried putting the project/ directory in the classpath as well, with no luck.
How do you set up a simple clojure project?
You don't mention what your environment is (i.e. Emacs/SLIME/Swank, vim/Vimclojure), so I'm going to assume you are trying to invoke it from the command line.
You need to have your Clojure/ project directory in the classpath:
java -cp path/to/clojure.jar:path/to/clojure-contrib.jar:path/to/Clojure ...
Make sure to check that paths are correct relative to current working directory. It needs to point to the root of your namespace (i.e. if running in Clojure/, the path is .).
In fact, your project layout Works On My Machine(tm), with the exception that I have use instead of require (but you should've got a different error anyway if you got to the point when Clojure could find all your files).
This answer I posted to another question should hopefully give you an idea of how your filenames should relate to namespace names for things to work. However, since your question is "how to set up a simple Clojure project", the following is a better start:
Go to GitHub and grab Leiningen.
Follow the instructions in the README. You'll end up doing something like
$ lein new my-project
$ cd my-project
# ... edit project.clj ...
$ lein deps
Hack away! You'll need to put your files in the correct places. That will mean putting your source files in the directory tree rooted at my-project/src, with your core namespace most likely residing at my-project/src/my_project/core.clj. But really, I've explained all the details in the answer linked to above, so please read it (and do leave a comment if I missed something). :-)
Leiningen will take care of the basic project layout and setting up the classpath for a REPL / swank / nailgun for you (if you haven't yet come across the latter two, you will soon -- but that's a separate topic, the swank part of which I have covered to a certain degree e.g. in this SO answer), so hopefully you'll never need to deal with the java -cp ... nonsense by hand. (The swank-related answer I linked to in the last parenthetical remark has details on how to set up swank with the correct classpath from within Emacs.)