Slamhound

They sent a slamhound on Turner's trail in New Delhi, slotted it
to his pheromones and the color of his hair. It caught up with him
on a street called Chandni Chauk and came scrambling for his
rented BMW through a forest of bare brown legs and pedicab
tires. Its core was a kilogram of recrystallized hexogene and
flaked TNT. He didn't see it coming. The last he saw of India was
the pink stucco facade of a place called the Khush-Oil Hotel.

Because he had a good agent, he had a good contract. Because he
had a good contract, he was in Singapore an hour after the
explosion. Most of him, anyway. The Dutch surgeon liked to joke
about that, how an unspecified percentage of Turner hadn't made it
out of Palam International on that first flight and had to spend
the night there in a shed, in a support vat.

It took the Dutchman and his team three months to put Turner
together again. They cloned a square meter of skin for him, grew
it on slabs of collagen and shark-cartilage polysaccharides. They
bought eyes and genitals on the open market. The eyes were green.

-- Count Zero, page 1. By William Gibson

Slamhound rips your ns form apart and reconstructs it. No Dutch surgeon required.

Install it as a Leiningen plugin:

$ lein plugin install slamhound 1.2.0

Leiningen Usage

Take a namespace with a sparse ns form that won't compile:

$ cat src/my/namespace.clj # before: ns form is missing clauses

(ns my.namespace
  "I have a docstring.")

(defn -main [& args]
  (pprint args)
  (io/copy (ByteArrayInputStream. (.getBytes "hello"))
           (first args)))

Then run slamhound on it:

$ lein slamhound src/my/namespace.clj # after: spits out new ns form

(ns my.namespace
  "I have a doc string."
  (:use [clojure.pprint :only [pprint]])
  (:require [clojure.java.io :as io])
  (:import (java.io ByteArrayInputStream)))

For large projects, it can be slow to re-run from the command-line since it has to load every namespace for every invocation. Leiningen's interactive task is one way to mitigate this:

$ lein int
Welcome to Leiningen. Type help for a list of commands.
lein> slamhound src/my/namespace.clj
[...]

The first run will be slow, but successive runs will be quick.

Repl Usage

You can do it manually from the repl too:

user=> (use 'slam.hound)
nil
user=> (println (reconstruct "src/my/namespace.clj"))
(ns my.namespace
  "I have a doc string."
  (:use [clojure.pprint :only [pprint]])
  (:require [clojure.java.io :as io])
  (:import (java.io ByteArrayInputStream)))

Emacs Usage

The included src/swank/payload/slamhound.el allows for convenient access within Slime sessions via M-x slamhound as well as running it over an entire project with M-x slamhound-project.

You can install manually, but if you use M-x clojure-jack-in with Swank Clojure 1.3.3 or newer to launch your Slime session then it will be loaded into Emacs automatically.

Emacs version 24 or greater is required.

The Rules

Slamhound can only rebuild your namespace if it follows the rules and doesn't do anything too fancy. If your code depends upon a :require clause, the required namespace must be aliased :as the last segment of its name. Referring to fully-qualified vars is not supported. The only supported option to :use is :only.

Future Plans

Better pretty-printing
Allow for custom disambiguator functions

License

Distributed under the Eclipse Public License, the same as Clojure.