From c5cba1d7163157ce8da4ea012e0e7443d000a30a Mon Sep 17 00:00:00 2001
From: Alexander Nozik <altavir@gmail.com>
Date: Thu, 18 Mar 2021 16:00:05 +0300
Subject: [PATCH] lesson2

---
 src/main/kotlin/lesson2/idiom14-15.kt | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/src/main/kotlin/lesson2/idiom14-15.kt b/src/main/kotlin/lesson2/idiom14-15.kt
index 38b1493..c73c8fa 100644
--- a/src/main/kotlin/lesson2/idiom14-15.kt
+++ b/src/main/kotlin/lesson2/idiom14-15.kt
@@ -1,9 +1,26 @@
 package lesson2
 
+/**
+ * Extension property on a String. It is not monkey-patching.
+ */
 fun String.countOs(): Int = count { it == 'о' } // implicit this points to String
 
 fun Int.printMe() = println(this) // explicit this
 
 fun main() {
     "обороноспособность".countOs().printMe()
-}
\ No newline at end of file
+}
+
+/**
+ * Extension property (must be virtual)
+ */
+val List<Int>.odd get() = filter { it % 2 == 1 }
+
+/**
+ * Extension variable (also must be virtual)
+ */
+var Array<Int>.second: Int
+    get() = get(1)
+    set(value) {
+        set(1, value)
+    }
\ No newline at end of file