#SICP in Clojure

##About This is a version of the classic Structure and Interpretation of Computer Programs by Hal Abelson and Jerry & Julie Sussman, revised with code examples in Clojure instead of the original Scheme.

##Read If you'd just like to read the book, visit the site here.

##Contribute The code samples and chapter text are available in this repository, so you can contribute to the project yourself. If you see an example that could be improved, want to add a footnote or aside about Clojure, or want to jump in and edit one of the uncompleted chapters, please make a fix and submit a pull request.

###Editing guidelines The source text is in the resources/text directory, with filenames corresponding to the pages of the original book's website. These files are all in standard markdown, with three extra elements:

Inline footnotes are indicated by [^fn-#], where # is the footnote number in the original text. The corresponding anchor at the bottom of the page is indicated by [fn-#]:

We will use block structure extensively to help us break up large programs
into tractable pieces.[^fn-28]

[fn-28] Embedded definitions must come first in a procedure body. The 
management is not responsible for the consequences of running programs that 
intertwine definition and use.

Code blocks are represented by sequential filenames inside double curly braces. For example:

A second advantage of prefix notation is that it extends in a straightforward
way to allow combinations to be _nested_, that is, to have combinations whose
elements are themselves combinations:

{{ 1.1.1.5.clj }}

There is no limit (in principle) to the depth of such nesting and to the
overall complexity of the expressions that the Lisp interpreter can evaluate.
It is we humans who get confused by still relatively simple expressions such
as

{{ 1.1.1.6.clj }}

which the interpreter would readily evaluate to be 57.

These correspond to .clj files in resources/code. Code blocks are labeled sequentially according to their location in the text, e.g., the third figure in section 1.1.7 is 1.1.7.3.clj.

Math uses MathJax syntax, which includes most of your favorite LaTex symbols. Blocks of math are wrapped in \\[ and \\]:

In general, the Fibonacci numbers can be defined by the rule

\\[ \text{Fib}(n) = 
\begin{cases}
 0 & \text {if } n = 0 \\\\
 1 & \text{if }  n = 1 \\\\ 
 \text{Fib}(n-1) + \text{Fib}(n-2) & \text{otherwise} 
\end{cases} \\]

Inline expressions are wrapped in \\( and \\):

**Exercise 1.13.**  Prove that _Fib_(_n_) is the closest integer to \\( \phi^{n} / \sqrt{5} \\),
where \\( \phi = (1 + \sqrt{5})/2 \\) Hint: Let \\( \psi= (1 - \sqrt{5}) / {2} \\).

Be careful! You'll need to escape any characters that are also markdown symbols with a backslash. The most common are the underscore ("k sub one" is thus \\( k\_{1} \\)), and the double-backslash, used to separate rows in a matrix or system of equations (so \\ becomes \\\\). I usually use this MathJax test site for reference, then add the extra escape characters.

Finally, figures are stored in resources/static/img/, with their original labels from the source text. I've been using .png images drawn up with Google Docs, but make your own however you'd like. Text is in Ubuntu Mono and colors are from the Solarized color scheme. Transparent backgrounds work best.

###Previewing your edits I haven't packaged this as a library, and probably won't, but if you want to check out your extra-escaped backslashes or simply admire your handiwork, it's pretty easy to run it through the site generator from the REPL:

git clone git://github.com/ecmendenhall/sicpclojure.git 
cd sicpclojure
lein deps
lein repl

Open src/sicpclojure/config.clj and add the pages you'd like to preview to the :complete vector:

(def build {:path-to-code "resources/code/" ; Path to code excerpts.
            :path-to-text "resources/text/" ; Path to chapter text.
            :deploy-directory "deploy/"     
            :ignore #{".scss"}              ; Ignore these filetypes when deploying.
            :complete [9 10 11 12]})        ; Vector of completed pages. <--- This one!

Slurp src/sicpclojure/core.clj into your REPL, then:

(dev-server)

This will generate the page and start a simple Jetty server. Your edits should now be available as beautiful full-color HTML via localhost:3000.

##License The SICP text is licensed under a Creative Commons BY-SA 3.0 license (so the source text in this repository is too). My code is released under an MIT license. If you would like to read one, see the file LICENSE.md!

This site also uses Requirejs, MathJax, Highlight.js, Google Web Fonts, and the Solarized sass template, plus the pegdown markdown processor, Hiccup templates, and the Hickory HTML to Hiccup parser.