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<!doctype html>
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<html>
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<head>
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<meta charset="utf-8">
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<meta http-equiv="X-UA-Compatible" content="IE=edge">
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<meta name="viewport" content="width=device-width, initial-scale=1">
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<title>My Learning Website</title>
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<link href="/styles/styles.css" rel="stylesheet" type="text/css">
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<link href="/android/styles/styles.css" rel="stylesheet" type="text/css">
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<!-- HTML5 shim and Respond.js for IE8 support of HTML5 elements and media queries -->
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<!-- WARNING: Respond.js doesn't work if you view the page via file:// -->
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<!--[if lt IE 9]>
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<script src="https://oss.maxcdn.com/html5shiv/3.7.2/html5shiv.min.js"></script>
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<script src="https://oss.maxcdn.com/respond/1.4.2/respond.min.js"></script>
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<![endif]-->
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</head>
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<body>
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<div class="banner">
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<h1 class="courselink"><a href="https://www.linkedin.com/learning/kotlin-essential-training-2018">Kotlin Essential Training</a></h1>
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<h2 class="lecturer">LinkedIn Learning : David Gassner : March 2018</h2>
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<h2 class="episodetitle">Code Sample</h2>
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</div>
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<article>
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<h2 class="sectiontitle">Chapter 4 - Section 4</h2>
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<pre class="inset">
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fun main(args: Array<String>) {
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var nullValue:String? = null
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println(nullValue)
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val l:Int? = nullValue?.length
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println("Length is $l")
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if (l == null) {
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println("Length is null")
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}
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val message = if (l != null) {
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"Length: $l"
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} else {
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"l is null"
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}
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println(message)
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val l2 = l ?: -1
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println("The value of l2 is $l2")
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try {
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val l3 = l!!
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println("The value of l3 is $l3")
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} catch (e: KotlinNullPointerException) {
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println("l3 is null")
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}
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}</pre>
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</article>
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<div class="btngroup">
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<button class="button" onclick="window.location.href='setting.html';">
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Chapter 1
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</button>
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<button class="button" onclick="window.location.href='getstarted.html'">
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Chapter 2
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</button>
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<button class="button" onclick="window.location.href='variables.html'">
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Chapter 3
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</button>
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<button class="button" onclick="window.location.href='flow.html'">
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Chapter 4
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</button>
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<button class="button" onclick="window.location.href='classes.html'">
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Chapter 5
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</button>
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<button class="button" onclick="window.location.href='data.html'">
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Chapter 6
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</button>
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<button class="button" onclick="window.location.href='inheritance.html'">
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Chapter 7
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</button>
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<button class="button" onclick="window.location.href='appendixa.html'">
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Appendix A
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</button>
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<button class="button" onclick="window.location.href='appendixb.html'">
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Appendix B
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</button>
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<button class="button" onclick="window.location.href='code.html'">
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Code Samples
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</button>
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<button class="button" onclick="window.location.href='/android/android.html'">
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Android Page
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</button>
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<button class="button" onclick="window.location.href='/index.html'">
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Home
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</button>
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</div>
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</body>
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</html>
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