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* Replace tiny bitmaps with base64-encoded URIs
* Optimize SVGs; replace logo PNG with SVG
* Modernize favicon
* Embed CSS; a bit unorthodox, but we’re a single page so there’s no point in separate .css files and their separate HTTP requests
* Documentation is now markdown, converted to HTML on compilation
* Render the examples when we’re rendering index.html; they compile so quickly that there’s no need to pre-render them and save the intermediate .js files
* Split apart index.html into components that Cakefile assembles, so that we can add in logic to include different files for v1 versus v2
* Split building index.html and building test.html into two tasks; collapse the parts of `releaseHeader` into one compact function
* Move include logic into templates
* Get error messages tests to work in the browser
* Update output index.html
* Split body into nav and body
* Watch subtemplates
* Revert "Split body into nav and body"
This reverts commit ec9e559ec0.
* Add marked
* Update gitignore
* Use idiomatic markdown output for code blocks (<pre><code>)
* Handle ids within the template, not in the Cakefile; remove marked’s auto-generated and conflicting ids
* Move the `codeFor` function into versioned folders, so that v1 and v2 docs can have different example code blocks/editors
* Update packages, including new highlight.js which supports our newer keywords and triple backticks (docs output is unchanged)
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Loops and Comprehensions
Most of the loops you’ll write in CoffeeScript will be comprehensions over arrays, objects, and ranges. Comprehensions replace (and compile into) for loops, with optional guard clauses and the value of the current array index. Unlike for loops, array comprehensions are expressions, and can be returned and assigned.
codeFor('array_comprehensions')
Comprehensions should be able to handle most places where you otherwise would use a loop, each/forEach, map, or select/filter, for example:
shortNames = (name for name in list when name.length < 5)
If you know the start and end of your loop, or would like to step through in fixed-size increments, you can use a range to specify the start and end of your comprehension.
codeFor('range_comprehensions', 'countdown')
Note how because we are assigning the value of the comprehensions to a variable in the example above, CoffeeScript is collecting the result of each iteration into an array. Sometimes functions end with loops that are intended to run only for their side-effects. Be careful that you’re not accidentally returning the results of the comprehension in these cases, by adding a meaningful return value — like true — or null, to the bottom of your function.
To step through a range comprehension in fixed-size chunks, use by, for example:
evens = (x for x in [0..10] by 2)
If you don’t need the current iteration value you may omit it:
browser.closeCurrentTab() for [0...count]
Comprehensions can also be used to iterate over the keys and values in an object. Use of to signal comprehension over the properties of an object instead of the values in an array.
codeFor('object_comprehensions', 'ages.join(", ")')
If you would like to iterate over just the keys that are defined on the object itself, by adding a hasOwnProperty check to avoid properties that may be inherited from the prototype, use for own key, value of object.
To iterate a generator function, use from. See Generator Functions.
The only low-level loop that CoffeeScript provides is the while loop. The main difference from JavaScript is that the while loop can be used as an expression, returning an array containing the result of each iteration through the loop.
codeFor('while', 'lyrics.join("\\n")')
For readability, the until keyword is equivalent to while not, and the loop keyword is equivalent to while true.
When using a JavaScript loop to generate functions, it’s common to insert a closure wrapper in order to ensure that loop variables are closed over, and all the generated functions don’t just share the final values. CoffeeScript provides the do keyword, which immediately invokes a passed function, forwarding any arguments.
codeFor('do')