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* Move analytics initialization into docs.coffee * Bump Bootstrap and CodeMirror versions * Update output * Merge CodeMirror styles * Update CodeMirror styles * Better flexbox layout for docs, including flex auto-sized sidebar and main column * Minor styling fixes for Edge * Fix scrollspy for new layout * Update output * Clicking on the CoffeeScript logo in the navbar should scroll to top; fix main column width on mobile * Update output * 2.3.0 changelog * Update operators section for ** * Update docs for ES2018 object rest/spread * Remove references to Node's experimental modules support * Move the README coffee cup to the right side, so our name isn't cut off on the NPM page; update README and CONTRIBUTING text * Update dependencies * Add compatibility note for async generators * Bump version to 2.3.0 and update output * Have CI test in Node 10 instead of 9 * Somehow this gets generated slightly differently in Node 10 * Fix #4042: Update broken link
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Bound (Fat Arrow) Functions
In JavaScript, the this keyword is dynamically scoped to mean the object that the current function is attached to. If you pass a function as a callback or attach it to a different object, the original value of this will be lost. If you’re not familiar with this behavior, this Digital Web article gives a good overview of the quirks.
The fat arrow => can be used to both define a function, and to bind it to the current value of this, right on the spot. This is helpful when using callback-based libraries like Prototype or jQuery, for creating iterator functions to pass to each, or event-handler functions to use with on. Functions created with the fat arrow are able to access properties of the this where they’re defined.
codeFor('fat_arrow')
If we had used -> in the callback above, @customer would have referred to the undefined “customer” property of the DOM element, and trying to call purchase() on it would have raised an exception.
The fat arrow was one of the most popular features of CoffeeScript, and ES2015 adopted it; so CoffeeScript 2 compiles => to ES =>.