Giters

mikera / pomegranate

Geek Repo:Geek Repo

Github PK Tool:Github PK Tool

Pomegranate

Pomegranate is a library that provides:

  1. A very, very incomplete wrapper for Sonatype Aether — really, just dependency resolution at this point.

  2. A re-implementation of add-classpath (deprecated in Clojure core) that:

    • is a little more comprehensive than core’s add-classpath — it should work as expected in more circumstances, and

    • optionally uses Aether to add a Maven artifact (and all of its transitive dependencies) to your Clojure runtime’s classpath dynamically.

Insofar as most useful Clojure libraries have dependencies, any reasonable implementation of the add-classpath concept must seamlessly support resolving those dependencies IMO.

Status

This library is functionally completely new; literally, v0.0.1. There will be changes. In any case, it’s obviously incomplete.

"Installation"

Pomegranate is available in Maven central. Add it to your Leiningen/Cake project.clj:

[com.cemerick/pomegranate "0.0.1"]

or to your Maven project’s pom.xml:

<dependency>
  <groupId>com.cemerick</groupId>
  <artifactId>pomegranate</artifactId>
  <version>0.0.1</version>
</dependency>

Usage

Just to set a stage: you’re at the REPL, and you’ve got some useful data that you’d like to munge and analyze in various ways. Maybe it’s something you’ve generated locally, maybe it’s data on a production machine and you’re logged in via nREPL. In any case, you’d like to work with the data, but realize that you don’t have the libraries you need do what you want. Your choices at this point are:

  1. Dump the data to disk via pr (assuming it’s just Clojure data structures!), and start up a new Clojure process with the appropriate libraries on the classpath. This can really suck if the data is in a remote environment.

  2. There is no second choice. You could use add-claspath, but the library you want has 12 bajillion dependencies, and there’s no way you’re going to hunt them down manually.

Let’s say we want to use [Incanter] (which has roughly 40 dependencies — close enough to a 12 bajillion for all practical purposes!):

=> (require '(incanter core stats charts))
#<CompilerException java.io.FileNotFoundException:
  Could not locate incanter/core__init.class or incanter/core.clj on classpath:  (NO_SOURCE_FILE:0)>

Looks bleak. Assuming you’ve got Pomegranate on your classpath already, you can do this though:

=> (add-dependencies '[[incanter "1.2.3"]]
                     :repositories {"clojars" "http://clojars.org/repo"})
nil
=> (require '(incanter core stats charts))
nil

Now you can analyze and chart away, Incanter having been added to your runtime. Note that add-dependencies may crunch along for a while — it may need to download dependencies, so you’re waiting on the network. All resolved dependencies are stored in the default local repository (~/.m2/repository), and if they are found there, then they are not downloaded.

The arguments to add-dependencies look like Leiningen-style notation, and they are. But support for that is definitely incomplete, e.g. repositories may only be string URLs (no authentication, mirroring, etc. is supported).

Need Help?

Ping cemerick on freenode irc or twitter if you have questions or would like to contribute patches.

License

Copyright © 2011 Chas Emerick

Licensed under the EPL. (See the file epl-v10.html.)

About