I am reading a Clojure book. I typed one of the examples into a file. How can I load it into a lein repl?
I don't have a lein project and would prefer not to create one.
lein repl (this will not create a lein project)
then in repl
user=> (load-file "yourfile.clj")
Related
I'm using cljx to build cli / cljs applications but haven't for the life of me been able to create a self packaged compiled jar.
Here's my project file -> https://gist.github.com/chrispwood/4db33e53555a8e8787d1
When I run lein jar or lein uberjar I get only a packaged jar with the clj files, not the class files. See the output file above ^^.
Does anyone know how to make sure the transpiled clj code gets compiled into class files?
When setting up a Clojure + ClojureScript project, most commonly, I've seen people put their Clojure source directory and their ClojureScript source directory on their project.clj's top-level :source-paths. For instance, Chestnut, a Clojure + ClojureScript template, uses:
:source-paths ["src/clj" "src/cljs"]
I may not understand Leiningen enough, but doesn't that just put those directories on the classpath? Why would you want your ClojureScript on the classpath? I would think that pointing cljsbuild at it and getting it to compile would be enough.
Adding the ClojureScript source tree to :source-paths is one of the simplest ways of ensuring that Leiningen includes it in jars and überjars. It is not adequate for all projects, however, and so ClojureScript libraries use all sorts of different arrangements.
If you're implementing a pure ClojureScript library, you may find it convenient to use the :source-paths approach – or you could place your .cljs files inside the default "src" directory.
If you're using cljx, you'll want to include the .clj and .cljs files it produces in your jars, so something like Sente's project.clj (link to version 1.1.0) may work better for you.
If you don't need to include your ClojureScript source files in your jars, you're free to mention your .cljs files to lein-cljsbuild only.
I've been learning clojure on the REPL environment with Clojure Box.
How can I make an executable file (.jar)?
I'm wondering if something like this is possible:
write clojure code on notepad and name it project.clj
compile project.clj
get executable file
Step #2 doesn't have to be done in command line. IDE is fine.
As Erhan Bagdemir answered, you should use Leiningen. Here's how I do it on Windows:
Install Leiningen on Windows
You're going to download the Leiningen script and put it somewhere on your PATH. If you have a folder already on your path that you use for executable scripts, if not, do the following:
Download the Leiningen package from Github.
Unzip it in your home folder (e.g. /Users/vikbehal)
Add the folder that was created by unzipping to your PATH. To do this, open the Control Panel, and go to the System area where you can edit your Environment Variables. Edit either the system or your user's PATH value by adding /Users/vikbehal/lein (or whatever the folder is called) to your PATH, making sure to keep that entry separated from others by a semicolon (;).
Press Ok to save your changes.
You can verify that you've successfully installed Leiningen by opening up a command prompt and running lein help. You should see Leiningen installing some initial files. If you get an error, make sure you've properly added the folder where Leiningen lives to your PATH.
Use Leiningen to Develop
Leiningen gives you a good default directory structure, handles dependency management, and ensures that Java's classpath is set properly when running a REPL or, in this case, jarring your application.
Here's a run-down of Leiningen standard commands:
# Start a blank project
lein new my-project
# Pull down dependencies defined in your project.clj file
lein deps
# Create a "library" jar of your project
lein jar
# Create an executable jar of your project
lein uberjar
It looks like that last command is what you want, right? First, you need to configure a few things, so that Leiningen can build your executable jar properly.
Configuring for an Executable/Standalone Jar
You need to do three things to make lein uberjar work properly:
Write a -main function that will act as the "entry point" to the execution of your jar file. (Note the -, it denotes that this function is more like a "Java method" than a regular Clojure function.)
Make sure you add a (:gen-class :main true) declaration in the ns namespace declaration at the top of the file that contains your -main function.
Add a :main my.main.namespace entry in your project.clj
Now run lein uberjar. While developing, you can alternatively use lein run if you want to test how your application would behave as an executable jar, but don't want to explicitly re-jar every time you make a change.
Use Leiningen to create an uberjar.
with Leiningen:
http://www.bagdemir.com/2011/07/04/creating-new-projects-with-leiningen/
Just for variety I though I would mention the maven clojure plugin for those who want to keep to their Java roots.
I've been learning some Clojure, and I currently have a single .clj file which I edit in a text editor and which I execute on the command line.
Where can I find a guide on the practical aspects of scaling this up to larger programs/libraries?
How should I lay out multiple .clj files on the filesystem?
How should I organize and execute test code?
How should I document the program/library?
How should I package it?
I'm looking for information on the practical aspects on scaling up from small scripts to something real.
I recommend using leiningen. Running
$ lein new myproject
will create a new folder called myproject inside your current working directory with a default skeleton structure.
Inside the newly generatedmyproject folder you'll find (among others) a folder named src for clojure source code and a folder named test for your tests (leiningen will generate a default failing test).
Leiningen will let you run your tests with lein test.
You can package your project as a jar file with lein jar or create an uberjar (an executable jar with all required dependencies included) with lein uberjar.
For generating documentation I recommend autodoc which integrates nicely with leiningen.
If you are using Netbeans, there is a Clojure plugin which could be helpful to you.
Creating a Clojure project with it creates a bunch of folders: Source Packages, which contains a default package called com.yourcompany, Test Packages, Libraries, which contains the .jar for Clojure and a link to the JDK, and Test Libraries, which contains JUnit.
I use a combo of:
Intellij Idea with the La Clojure plugin
Leiningen
Clojars
Midje, for testing/mocking
Git
Good luck!
What is the easiest way to make a clojure app into an executable like http://rawr.rubyforge.org/ does for ruby? (exe and app files too)
Use leiningen and build an uberjar(standalone jar that contains all dependencies) from the project.
As Alex Ott mentions in the comment to my answer, another may to build your app is to use Maven + Clojure plugin for maven. Afterward you may use a tool such as IzPack to generate an installer or an executable wrapper for your jar artifact. You may use IzPack with leiningen as well of course - it doesn't care about the build system at all - only about the resulting files :-)
After you have the uberjar there are many option to wrap it in a native executable launcher for windows - izpack2exe, jsmooth, jar2exe, executor, etc...
To expand on Bozhidar's answer leiningen makes it super easy to generate a jar that packages your app and its dependencies. Just run lein uberjar from the terminal when you are inside your project directory and it will create a file project-name-0.1.0-standalone.jar that can be run with java -jar where "project-name" is the name of your project. You want to make sure that is your project.clj you set :main to your file that has a -main function. Also in your main file you want to put (:gen-class) inside your namespace declaration like so:
(ns project-name.main
(: require ...)
(:gen-class))