90 lines
2.5 KiB
HTML
90 lines
2.5 KiB
HTML
<!doctype html>
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<html lang="en">
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<head>
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<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
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<title>Styleguide</title>
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<link rel="stylesheet" href="../lib/3rdparty/highlight/styles/default.css">
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<link rel="stylesheet" href="../css/doctest.css">
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<script src="./3rdparty/highlight/highlight.pack.js"></script>
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<script src="./3rdparty/all.js"></script>
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<script src="all.js"></script>
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</head>
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<body onload="Doctest.run()" >
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<h1>
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Styleguide
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</h1>
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<p id="paragraph">
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Modern JavaScript is more concise (some would say Pythonic) than ever. The
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language shows a clear trend to omit superfluous chars (e.g. the semicolon after
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each statement, a compact notation for multiline-strings) provide more specific
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keywords (e.g. let and const in addition to the var statement, class and static
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for object oriented programing and namespaces).
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This styleguide lists some of the newer ways which should be prefered over older
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styles still to be found on <a href="http://stackoverflow.com">stackoverflow</a>
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and other sites.
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</p>
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<script class="doctest">
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var a = 42 // Old way, global scope
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let b = 42 // New way, local scope
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const c = 42 // Use this for values that should remain constant
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// Commonly used but in modern browsers no longer needed
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let p = document.getElementById('paragraph')
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// Instead use id directly
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console.log(paragraph)
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// Iteration the old way
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let list = [a, b, c]
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for(var i=0; i<list.length; i++) {
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let value = list[i]
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}
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// Prefered shorter version
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for(let key of list) {
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let value = list[key]
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}
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// Anonymous functions the old way
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list.forEach(function(value) { })
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// Prefered arrow functions
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list.forEach((value) => { })
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// The main advantage of arrow functions is the fact that this is now
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// bound to the value in the outer context. This makes bind calls superfluous.
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class Test {
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obsolete1() {
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this.addEventListener(function(event) {
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console.log("This is still this:", this)
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}.bind(this))
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}
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obsolete2() {
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var that = this
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this.addEventListener(function(event) {
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console.log("This is still that:", that)
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})
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}
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method() {
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this.addEventListener((event) => {
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console.log("This is still this:", this)
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})
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}
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}
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</script>
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<p>The same holds for HTML5.</p>
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<pre><code>
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<!-- Old way -->
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<script type="text/javascript" src=""></script>
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<!-- Prefered way: text/javascript is now the default type -->
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<script src=""></script>
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</code></pre>
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</body>
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