Completed Coursera: Kotlin for developers course

src/With.kt

@@ -0,0 +1,33 @@
+fun main() {
+    val sb = StringBuilder()
+    // sb becomes this within the lambda scope
+    val string = with(sb) /* Is an extention function on type T */ {
+        appendLine("Something")
+        append('a')
+        toString()
+    }
+
+    val buildString = buildString {
+        append(1)
+        append(2)
+        toString()
+    }
+
+    val words = Words()
+    with(words) {
+        // The following two lines should compile:
+        "one".record()
+        +"two"
+    }
+    words.toString() == "[one, two]"
+}
+
+class Words {
+    private val list = mutableListOf<String>()
+
+    fun String.record() = list.add(this)
+
+    operator fun String.unaryPlus() = list.add(this)
+
+    override fun toString() = list.toString()
+}