stuarthalloway / programming-clojure

Sample code for the book

Sample Code for Programming Clojure

http://www.pragprog.com/titles/shcloj2/programming-clojure Copyright 2011 Stuart Halloway and Aaron Bedra. All rights reserved.

Important Notice

If you are reading the first edition of the book sure you grab the first-edition branch of this project instead, from

https://github.com/stuarthalloway/programming-clojure/tree/first-edition

The first-edition branch has all the files exactly where the book says they will be.

Getting Started

• Make sure you have Java installed.
• Make sure you have leiningen installed.
• Run lein deps to install all the dependent libraries.
• Run script/repl to launch a repl.

Want more Clojure Practice?

Labrepl is a free, open-source environment for exploring the Clojure language. It includes:

• a web application that presents a set of lab exercises with step-by-step instructions
• an interactive repl for working with the lab exercises
• solutions with passing tests
• up-to-date versions of Clojure, contrib, incanter, compojure and other libraries to explore

programming-clojure's Issues

Untitled

Clojure binding not working ,is bug?

user=>(loop [x 5 result []]
(do (println x result))
(if (zero? x)
result
(recur (conj result x) (dec x) )))

------------output-----------------------------------
5 []
[5] 4
ClassCastException clojure.lang.PersistentVector cannot be cast to java.lang.Num
ber clojure.lang.Numbers.isZero (Numbers.java:92)

---

why?

clojure contrib issue

I'm getting:

Downloading: org/clojure/contrib/standalone/1.3.0-SNAPSHOT/standalone-1.3.0-SNAPSHOT.pom from repository clojars at http://clojars.org/repo/
Unable to locate resource in repository
[INFO] Unable to find resource 'org.clojure.contrib:standalone:pom:1.3.0-SNAPSHOT' in repository clojars (http://clojars.org/repo/)
Downloading: org/clojure/contrib/standalone/1.3.0-SNAPSHOT/standalone-1.3.0-SNAPSHOT.jar from repository clojars at http://clojars.org/repo/
Unable to locate resource in repository
[INFO] Unable to find resource 'org.clojure.contrib:standalone:jar:1.3.0-SNAPSHOT' in repository clojars (http://clojars.org/repo/)
An error has occurred while processing the Maven artifact tasks.
Diagnosis:

Unable to resolve artifact: Missing:
----------
1) org.clojure.contrib:standalone:jar:1.3.0-SNAPSHOT

Try downloading the file manually from the project website.

Do I need to install it manually?

LICENSE is now a link to Stu's hard drive

lrwxr-xr-x   1 mtnygard  staff    52 May 28 10:19 LICENSE -> /Users/stuart/repos/shcloj/Book/code/README.markdown

Funnily enough, it doesn't resolve for me. :-)

Issues and pull requests?

I'm working through the book and the examples (I'm one of the tech reviewers) and was wondering if you are interested in getting issues or pull requests on this repo, or should I just make note of things and send them in my tech. review? I'd be glad to do either.

geting started launch code needs to change to 'lein repl'

In the Getting Started part of the project documentation, the launch code after 'lein deps' still asks user to run 'script/repl', should say run 'lein deps' as in the edition 2 book...

Clojure 1.1.0-alpha-SNAPSHOT included in this repo doesn't work with book (bindings broken)

The following example (based on page 173's let vs binding examples, doesn't work with the version of clojure (1.1.0-alpha) that is included in the book repo

(def foo 10)

(defn printfoo [](println foo))

(printfoo)

(binding [foo "bound foo"] (printfoo))

expected out put: "10" "bound foo"
what you get is: "10" "10"
clojure 1.0 (from clojure.org) works fine

Possible Fibo improvement (Page 95)

Wouldn't it be better to define Fibo as a simple sequence rather than a function here: https://github.com/stuarthalloway/programming-clojure/blob/master/src/examples/functional.clj#L45-L46

I mean:
(def fibo (map first (iterate (fn [[a b]] [b (+ a b)]) [0N 1N])))

This way I can "query" the data structure with
(take 10 fibo)

With the function form I am not really sure how to make it return only the first nth items.

Thanks for your book btw, I am greatly enjoying working with it.