From ad3fe3d536b591014dc0e9d6dc07a11918abdbd4 Mon Sep 17 00:00:00 2001
From: Rodrigo Graciano <rodrigolgraciano@gmail.com>
Date: Fri, 15 Feb 2019 23:43:15 -0500
Subject: [PATCH 1/4] BAEL-2648

---
 .../src/main/com/baeldung/range/CharRange.kt  | 13 +++++++++
 .../src/main/com/baeldung/range/Filter.kt     | 18 ++++++++++++
 .../src/main/com/baeldung/range/FirstLast.kt  |  8 ++++++
 .../com/baeldung/range/OtherRangeFunctions.kt | 14 ++++++++++
 .../src/main/com/baeldung/range/Range.kt      | 28 +++++++++++++++++++
 .../main/com/baeldung/range/ReverseRange.kt   | 14 ++++++++++
 .../src/main/com/baeldung/range/Step.kt       | 15 ++++++++++
 .../src/main/com/baeldung/range/UntilRange.kt |  8 ++++++
 8 files changed, 118 insertions(+)
 create mode 100644 core-kotlin-2/src/main/com/baeldung/range/CharRange.kt
 create mode 100644 core-kotlin-2/src/main/com/baeldung/range/Filter.kt
 create mode 100644 core-kotlin-2/src/main/com/baeldung/range/FirstLast.kt
 create mode 100644 core-kotlin-2/src/main/com/baeldung/range/OtherRangeFunctions.kt
 create mode 100644 core-kotlin-2/src/main/com/baeldung/range/Range.kt
 create mode 100644 core-kotlin-2/src/main/com/baeldung/range/ReverseRange.kt
 create mode 100644 core-kotlin-2/src/main/com/baeldung/range/Step.kt
 create mode 100644 core-kotlin-2/src/main/com/baeldung/range/UntilRange.kt

diff --git a/core-kotlin-2/src/main/com/baeldung/range/CharRange.kt b/core-kotlin-2/src/main/com/baeldung/range/CharRange.kt
new file mode 100644
index 0000000000..3151674d61
--- /dev/null
+++ b/core-kotlin-2/src/main/com/baeldung/range/CharRange.kt
@@ -0,0 +1,13 @@
+package com.baeldung.range
+
+fun main(args: Array<String>) {
+
+    for (ch in 'a'..'f') {
+        print(ch)
+    }
+    println()
+
+    for (ch in 'f' downTo 'a') {
+        print(ch)
+    }
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/main/com/baeldung/range/Filter.kt b/core-kotlin-2/src/main/com/baeldung/range/Filter.kt
new file mode 100644
index 0000000000..0e611b14cf
--- /dev/null
+++ b/core-kotlin-2/src/main/com/baeldung/range/Filter.kt
@@ -0,0 +1,18 @@
+package com.baeldung.range
+
+fun main(args: Array<String>) {
+    val r = 1..10
+
+    //Apply filter
+    val f = r.filter { it -> it % 2 == 0 }
+    println(f)
+
+    //Map
+    val m = r.map { it -> it * it }
+    println(m)
+
+    //Reduce
+    val rdc = r.reduce { a, b -> a + b }
+    println(rdc)
+
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/main/com/baeldung/range/FirstLast.kt b/core-kotlin-2/src/main/com/baeldung/range/FirstLast.kt
new file mode 100644
index 0000000000..b82f5a8b9b
--- /dev/null
+++ b/core-kotlin-2/src/main/com/baeldung/range/FirstLast.kt
@@ -0,0 +1,8 @@
+package com.baeldung.range
+
+fun main(args: Array<String>) {
+
+    println((1..9).first)
+    println((1..9 step 2).step)
+    println((3..9).reversed().last)
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/main/com/baeldung/range/OtherRangeFunctions.kt b/core-kotlin-2/src/main/com/baeldung/range/OtherRangeFunctions.kt
new file mode 100644
index 0000000000..19dcab89b2
--- /dev/null
+++ b/core-kotlin-2/src/main/com/baeldung/range/OtherRangeFunctions.kt
@@ -0,0 +1,14 @@
+package com.baeldung.range
+
+fun main(args: Array<String>) {
+
+    val r = 1..20
+    println(r.min())
+    println(r.max())
+    println(r.sum())
+    println(r.average())
+    println(r.count())
+
+    val repeated = listOf(1, 1, 2, 4, 4, 6, 10)
+    println(repeated.distinct())
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/main/com/baeldung/range/Range.kt b/core-kotlin-2/src/main/com/baeldung/range/Range.kt
new file mode 100644
index 0000000000..c313181599
--- /dev/null
+++ b/core-kotlin-2/src/main/com/baeldung/range/Range.kt
@@ -0,0 +1,28 @@
+package com.baeldung.range
+
+fun main(args: Array<String>) {
+
+    for (i in 1..9) {
+        print(i)
+    }
+    println()
+
+    for (i in 9 downTo 1) {
+        print(i)
+    }
+    println()
+
+    for (i in 1.rangeTo(9)) {
+        print(i)
+    }
+    println()
+
+    for (i in 9.downTo(1)) {
+        print(i)
+    }
+    println()
+
+    for (i in 1 until 9) {
+        print(i)
+    }
+}
diff --git a/core-kotlin-2/src/main/com/baeldung/range/ReverseRange.kt b/core-kotlin-2/src/main/com/baeldung/range/ReverseRange.kt
new file mode 100644
index 0000000000..875cf62200
--- /dev/null
+++ b/core-kotlin-2/src/main/com/baeldung/range/ReverseRange.kt
@@ -0,0 +1,14 @@
+package com.baeldung.range
+
+fun main(args: Array<String>) {
+
+    (1..9).reversed().forEach {
+        print(it)
+    }
+
+    println()
+
+    (1..9).reversed().step(3).forEach {
+        print(it)
+    }
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/main/com/baeldung/range/Step.kt b/core-kotlin-2/src/main/com/baeldung/range/Step.kt
new file mode 100644
index 0000000000..b9c5d48588
--- /dev/null
+++ b/core-kotlin-2/src/main/com/baeldung/range/Step.kt
@@ -0,0 +1,15 @@
+package com.baeldung.range
+
+fun main(args: Array<String>) {
+
+    for(i in 1..9 step 2){
+        print(i)
+    }
+
+    println()
+
+    for (i in 9 downTo 1 step 2){
+        print(i)
+    }
+
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/main/com/baeldung/range/UntilRange.kt b/core-kotlin-2/src/main/com/baeldung/range/UntilRange.kt
new file mode 100644
index 0000000000..2c116a286f
--- /dev/null
+++ b/core-kotlin-2/src/main/com/baeldung/range/UntilRange.kt
@@ -0,0 +1,8 @@
+package com.baeldung.range
+
+fun main(args: Array<String>) {
+
+    for (i in 1 until 9) {
+        print(i)
+    }
+}
\ No newline at end of file

From bad8753fd17cad0f3474914435fc81ddba4f9e76 Mon Sep 17 00:00:00 2001
From: Rodrigo Graciano <rodrigolgraciano@gmail.com>
Date: Mon, 18 Feb 2019 22:41:01 -0500
Subject: [PATCH 2/4] BAEL-2648

---
 core-kotlin-2/pom.xml                         | 64 ++++++++++++++++++-
 .../com/baeldung/range/CharRange.kt           |  0
 .../{ => kotlin}/com/baeldung/range/Filter.kt |  0
 .../com/baeldung/range/FirstLast.kt           |  0
 .../com/baeldung/range/OtherRangeFunctions.kt |  0
 .../{ => kotlin}/com/baeldung/range/Range.kt  |  0
 .../com/baeldung/range/ReverseRange.kt        |  0
 .../{ => kotlin}/com/baeldung/range/Step.kt   |  0
 .../com/baeldung/range/UntilRange.kt          |  0
 .../com/baeldung/range/CharRangeTest.kt       | 17 +++++
 .../kotlin/com/baeldung/range/FilterTest.kt   | 24 +++++++
 .../com/baeldung/range/FirstLastTest.kt       | 22 +++++++
 .../baeldung/range/OtherRangeFunctionsTest.kt | 40 ++++++++++++
 .../kotlin/com/baeldung/range/RangeTest.kt    | 22 +++++++
 .../com/baeldung/range/ReverseRangeTest.kt    | 12 ++++
 .../kotlin/com/baeldung/range/StepTest.kt     | 17 +++++
 .../com/baeldung/range/UntilRangeTest.kt      | 12 ++++
 17 files changed, 229 insertions(+), 1 deletion(-)
 rename core-kotlin-2/src/main/{ => kotlin}/com/baeldung/range/CharRange.kt (100%)
 rename core-kotlin-2/src/main/{ => kotlin}/com/baeldung/range/Filter.kt (100%)
 rename core-kotlin-2/src/main/{ => kotlin}/com/baeldung/range/FirstLast.kt (100%)
 rename core-kotlin-2/src/main/{ => kotlin}/com/baeldung/range/OtherRangeFunctions.kt (100%)
 rename core-kotlin-2/src/main/{ => kotlin}/com/baeldung/range/Range.kt (100%)
 rename core-kotlin-2/src/main/{ => kotlin}/com/baeldung/range/ReverseRange.kt (100%)
 rename core-kotlin-2/src/main/{ => kotlin}/com/baeldung/range/Step.kt (100%)
 rename core-kotlin-2/src/main/{ => kotlin}/com/baeldung/range/UntilRange.kt (100%)
 create mode 100644 core-kotlin-2/src/test/kotlin/com/baeldung/range/CharRangeTest.kt
 create mode 100644 core-kotlin-2/src/test/kotlin/com/baeldung/range/FilterTest.kt
 create mode 100644 core-kotlin-2/src/test/kotlin/com/baeldung/range/FirstLastTest.kt
 create mode 100644 core-kotlin-2/src/test/kotlin/com/baeldung/range/OtherRangeFunctionsTest.kt
 create mode 100644 core-kotlin-2/src/test/kotlin/com/baeldung/range/RangeTest.kt
 create mode 100644 core-kotlin-2/src/test/kotlin/com/baeldung/range/ReverseRangeTest.kt
 create mode 100644 core-kotlin-2/src/test/kotlin/com/baeldung/range/StepTest.kt
 create mode 100644 core-kotlin-2/src/test/kotlin/com/baeldung/range/UntilRangeTest.kt

diff --git a/core-kotlin-2/pom.xml b/core-kotlin-2/pom.xml
index 81df3cee81..e329611593 100644
--- a/core-kotlin-2/pom.xml
+++ b/core-kotlin-2/pom.xml
@@ -13,4 +13,66 @@
         <relativePath>../parent-kotlin</relativePath>
     </parent>
 
-</project>
+    <dependencies>
+        <dependency>
+            <groupId>org.jetbrains.kotlin</groupId>
+            <artifactId>kotlin-stdlib-jdk8</artifactId>
+            <version>${kotlin.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.junit.platform</groupId>
+            <artifactId>junit-platform-runner</artifactId>
+            <version>${junit.platform.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj.version}</version>
+            <scope>test</scope>
+        </dependency>
+        <dependency>
+            <groupId>org.jetbrains.kotlin</groupId>
+            <artifactId>kotlin-test</artifactId>
+            <version>${kotlin.version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.jetbrains.kotlin</groupId>
+                <artifactId>kotlin-maven-plugin</artifactId>
+                <version>${kotlin.version}</version>
+                <executions>
+                    <execution>
+                        <id>compile</id>
+                        <phase>compile</phase>
+                        <goals>
+                            <goal>compile</goal>
+                        </goals>
+                    </execution>
+                    <execution>
+                        <id>test-compile</id>
+                        <phase>test-compile</phase>
+                        <goals>
+                            <goal>test-compile</goal>
+                        </goals>
+                    </execution>
+                </executions>
+                <configuration>
+                    <jvmTarget>1.8</jvmTarget>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+
+    <properties>
+        <kotlin.version>1.2.71</kotlin.version>
+        <junit.platform.version>1.1.1</junit.platform.version>
+        <junit.vintage.version>5.2.0</junit.vintage.version>
+        <assertj.version>3.10.0</assertj.version>
+    </properties>
+
+</project>
\ No newline at end of file
diff --git a/core-kotlin-2/src/main/com/baeldung/range/CharRange.kt b/core-kotlin-2/src/main/kotlin/com/baeldung/range/CharRange.kt
similarity index 100%
rename from core-kotlin-2/src/main/com/baeldung/range/CharRange.kt
rename to core-kotlin-2/src/main/kotlin/com/baeldung/range/CharRange.kt
diff --git a/core-kotlin-2/src/main/com/baeldung/range/Filter.kt b/core-kotlin-2/src/main/kotlin/com/baeldung/range/Filter.kt
similarity index 100%
rename from core-kotlin-2/src/main/com/baeldung/range/Filter.kt
rename to core-kotlin-2/src/main/kotlin/com/baeldung/range/Filter.kt
diff --git a/core-kotlin-2/src/main/com/baeldung/range/FirstLast.kt b/core-kotlin-2/src/main/kotlin/com/baeldung/range/FirstLast.kt
similarity index 100%
rename from core-kotlin-2/src/main/com/baeldung/range/FirstLast.kt
rename to core-kotlin-2/src/main/kotlin/com/baeldung/range/FirstLast.kt
diff --git a/core-kotlin-2/src/main/com/baeldung/range/OtherRangeFunctions.kt b/core-kotlin-2/src/main/kotlin/com/baeldung/range/OtherRangeFunctions.kt
similarity index 100%
rename from core-kotlin-2/src/main/com/baeldung/range/OtherRangeFunctions.kt
rename to core-kotlin-2/src/main/kotlin/com/baeldung/range/OtherRangeFunctions.kt
diff --git a/core-kotlin-2/src/main/com/baeldung/range/Range.kt b/core-kotlin-2/src/main/kotlin/com/baeldung/range/Range.kt
similarity index 100%
rename from core-kotlin-2/src/main/com/baeldung/range/Range.kt
rename to core-kotlin-2/src/main/kotlin/com/baeldung/range/Range.kt
diff --git a/core-kotlin-2/src/main/com/baeldung/range/ReverseRange.kt b/core-kotlin-2/src/main/kotlin/com/baeldung/range/ReverseRange.kt
similarity index 100%
rename from core-kotlin-2/src/main/com/baeldung/range/ReverseRange.kt
rename to core-kotlin-2/src/main/kotlin/com/baeldung/range/ReverseRange.kt
diff --git a/core-kotlin-2/src/main/com/baeldung/range/Step.kt b/core-kotlin-2/src/main/kotlin/com/baeldung/range/Step.kt
similarity index 100%
rename from core-kotlin-2/src/main/com/baeldung/range/Step.kt
rename to core-kotlin-2/src/main/kotlin/com/baeldung/range/Step.kt
diff --git a/core-kotlin-2/src/main/com/baeldung/range/UntilRange.kt b/core-kotlin-2/src/main/kotlin/com/baeldung/range/UntilRange.kt
similarity index 100%
rename from core-kotlin-2/src/main/com/baeldung/range/UntilRange.kt
rename to core-kotlin-2/src/main/kotlin/com/baeldung/range/UntilRange.kt
diff --git a/core-kotlin-2/src/test/kotlin/com/baeldung/range/CharRangeTest.kt b/core-kotlin-2/src/test/kotlin/com/baeldung/range/CharRangeTest.kt
new file mode 100644
index 0000000000..0e23f508b6
--- /dev/null
+++ b/core-kotlin-2/src/test/kotlin/com/baeldung/range/CharRangeTest.kt
@@ -0,0 +1,17 @@
+package com.baeldung.range
+
+import org.junit.Test
+import kotlin.test.assertEquals
+
+class CharRangeTest {
+
+    @Test
+    fun testCharRange() {
+        assertEquals(listOf('a', 'b', 'c'), ('a'..'c').toList())
+    }
+
+    @Test
+    fun testCharDownRange() {
+        assertEquals(listOf('c', 'b', 'a'), ('c'.downTo('a')).toList())
+    }
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/test/kotlin/com/baeldung/range/FilterTest.kt b/core-kotlin-2/src/test/kotlin/com/baeldung/range/FilterTest.kt
new file mode 100644
index 0000000000..d0e2df8860
--- /dev/null
+++ b/core-kotlin-2/src/test/kotlin/com/baeldung/range/FilterTest.kt
@@ -0,0 +1,24 @@
+package com.baeldung.range
+
+import org.junit.Test
+import kotlin.test.assertEquals
+
+class FilterTest {
+
+    val r = 1..10
+
+    @Test
+    fun filterTest() {
+        assertEquals(listOf(2, 4, 6, 8, 10), r.filter { it -> it % 2 == 0 }.toList())
+    }
+
+    @Test
+    fun mapTest() {
+        assertEquals(listOf(1, 4, 9, 16, 25, 36, 49, 64, 81, 100), r.map { it -> it * it }.toList())
+    }
+
+    @Test
+    fun reduceTest() {
+        assertEquals(55, r.reduce { a, b -> a + b })
+    }
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/test/kotlin/com/baeldung/range/FirstLastTest.kt b/core-kotlin-2/src/test/kotlin/com/baeldung/range/FirstLastTest.kt
new file mode 100644
index 0000000000..ca797e9c9b
--- /dev/null
+++ b/core-kotlin-2/src/test/kotlin/com/baeldung/range/FirstLastTest.kt
@@ -0,0 +1,22 @@
+package com.baeldung.range
+
+import org.junit.Test
+import kotlin.test.assertEquals
+
+class FirstLastTest {
+
+    @Test
+    fun testFirst() {
+        assertEquals(1, (1..9).first)
+    }
+
+    @Test
+    fun testLast() {
+        assertEquals(9, (1..9).last)
+    }
+
+    @Test
+    fun testStep() {
+        assertEquals(2, (1..9 step 2).step)
+    }
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/test/kotlin/com/baeldung/range/OtherRangeFunctionsTest.kt b/core-kotlin-2/src/test/kotlin/com/baeldung/range/OtherRangeFunctionsTest.kt
new file mode 100644
index 0000000000..d2d36bbfae
--- /dev/null
+++ b/core-kotlin-2/src/test/kotlin/com/baeldung/range/OtherRangeFunctionsTest.kt
@@ -0,0 +1,40 @@
+package com.baeldung.range
+
+import org.junit.Test
+import kotlin.test.assertEquals
+
+class OtherRangeFunctionsTest {
+
+    val r = 1..20
+    val repeated = listOf(1, 1, 2, 4, 4, 6, 10)
+
+    @Test
+    fun testMin() {
+        assertEquals(1, r.min())
+    }
+
+    @Test
+    fun testMax() {
+        assertEquals(20, r.max())
+    }
+
+    @Test
+    fun testSum() {
+        assertEquals(210, r.sum())
+    }
+
+    @Test
+    fun testAverage() {
+        assertEquals(10.5, r.average())
+    }
+
+    @Test
+    fun testCount() {
+        assertEquals(20, r.count())
+    }
+
+    @Test
+    fun testDistinct() {
+        assertEquals(listOf(1, 2, 4, 6, 10), repeated.distinct())
+    }
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/test/kotlin/com/baeldung/range/RangeTest.kt b/core-kotlin-2/src/test/kotlin/com/baeldung/range/RangeTest.kt
new file mode 100644
index 0000000000..48fa483924
--- /dev/null
+++ b/core-kotlin-2/src/test/kotlin/com/baeldung/range/RangeTest.kt
@@ -0,0 +1,22 @@
+package com.baeldung.range
+
+import org.junit.Test
+import kotlin.test.assertEquals
+
+class RangeTest {
+
+    @Test
+    fun testRange() {
+        assertEquals(listOf(1,2,3), (1.rangeTo(3).toList()))
+    }
+
+    @Test
+    fun testDownTo(){
+        assertEquals(listOf(3,2,1), (3.downTo(1).toList()))
+    }
+
+    @Test
+    fun testUntil(){
+        assertEquals(listOf(1,2), (1.until(3).toList()))
+    }
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/test/kotlin/com/baeldung/range/ReverseRangeTest.kt b/core-kotlin-2/src/test/kotlin/com/baeldung/range/ReverseRangeTest.kt
new file mode 100644
index 0000000000..7e1c7badb7
--- /dev/null
+++ b/core-kotlin-2/src/test/kotlin/com/baeldung/range/ReverseRangeTest.kt
@@ -0,0 +1,12 @@
+package com.baeldung.range
+
+import org.junit.Test
+import kotlin.test.assertEquals
+
+class ReverseRangeTest {
+
+    @Test
+    fun reversedTest() {
+        assertEquals(listOf(9, 6, 3), (1..9).reversed().step(3).toList())
+    }
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/test/kotlin/com/baeldung/range/StepTest.kt b/core-kotlin-2/src/test/kotlin/com/baeldung/range/StepTest.kt
new file mode 100644
index 0000000000..4570ceeb0a
--- /dev/null
+++ b/core-kotlin-2/src/test/kotlin/com/baeldung/range/StepTest.kt
@@ -0,0 +1,17 @@
+package com.baeldung.range
+
+import org.junit.Test
+import kotlin.test.assertEquals
+
+class StepTest {
+
+    @Test
+    fun testStep() {
+        assertEquals(listOf(1, 3, 5, 7, 9), (1..9 step 2).toList())
+    }
+
+    @Test
+    fun testStepDown() {
+        assertEquals(listOf(9, 7, 5, 3, 1), (9 downTo 1 step 2).toList())
+    }
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/test/kotlin/com/baeldung/range/UntilRangeTest.kt b/core-kotlin-2/src/test/kotlin/com/baeldung/range/UntilRangeTest.kt
new file mode 100644
index 0000000000..f941c7f1e6
--- /dev/null
+++ b/core-kotlin-2/src/test/kotlin/com/baeldung/range/UntilRangeTest.kt
@@ -0,0 +1,12 @@
+package com.baeldung.range
+
+import org.junit.Test
+import kotlin.test.assertEquals
+
+class UntilRangeTest {
+
+    @Test
+    fun testUntil() {
+        assertEquals(listOf(1, 2, 3, 4), (1 until 5).toList())
+    }
+}
\ No newline at end of file

From b98294aaed0bf6cae91937b7f282c01f8b0e54b8 Mon Sep 17 00:00:00 2001
From: Rodrigo Graciano <rodrigolgraciano@gmail.com>
Date: Tue, 19 Feb 2019 23:01:34 -0500
Subject: [PATCH 3/4] BAEL-2648

---
 .../main/kotlin/com/baeldung/range/Color.kt   | 21 +++++++++++++++++++
 .../kotlin/com/baeldung/range/ColorTest.kt    | 20 ++++++++++++++++++
 2 files changed, 41 insertions(+)
 create mode 100644 core-kotlin-2/src/main/kotlin/com/baeldung/range/Color.kt
 create mode 100644 core-kotlin-2/src/test/kotlin/com/baeldung/range/ColorTest.kt

diff --git a/core-kotlin-2/src/main/kotlin/com/baeldung/range/Color.kt b/core-kotlin-2/src/main/kotlin/com/baeldung/range/Color.kt
new file mode 100644
index 0000000000..ef7adf06b5
--- /dev/null
+++ b/core-kotlin-2/src/main/kotlin/com/baeldung/range/Color.kt
@@ -0,0 +1,21 @@
+package com.baeldung.range
+
+enum class Color(val rgb: Int) {
+    BLUE(0x0000FF),
+    GREEN(0x008000),
+    RED(0xFF0000),
+    MAGENTA(0xFF00FF),
+    YELLOW(0xFFFF00);
+}
+
+fun main(args: Array<String>) {
+
+    println(Color.values().toList());
+    val red = Color.RED
+    val yellow = Color.YELLOW
+    val range = red..yellow
+
+    println(range.contains(Color.MAGENTA))
+    println(range.contains(Color.BLUE))
+    println(range.contains(Color.GREEN))
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/test/kotlin/com/baeldung/range/ColorTest.kt b/core-kotlin-2/src/test/kotlin/com/baeldung/range/ColorTest.kt
new file mode 100644
index 0000000000..4ac3270fcc
--- /dev/null
+++ b/core-kotlin-2/src/test/kotlin/com/baeldung/range/ColorTest.kt
@@ -0,0 +1,20 @@
+package com.baeldung.range
+
+import org.junit.Test
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+class ColorTest {
+
+    @Test
+    fun testEnumRange() {
+
+        println(Color.values().toList());
+        val red = Color.RED
+        val yellow = Color.YELLOW
+        val range = red..yellow
+
+        assertTrue { range.contains(Color.MAGENTA) }
+        assertFalse { range.contains(Color.BLUE) }
+    }
+}
\ No newline at end of file

From da2f95bfa39dc24a8a12750e28497618c67eb41d Mon Sep 17 00:00:00 2001
From: Rodrigo Graciano <rodrigolgraciano@gmail.com>
Date: Sun, 10 Mar 2019 20:34:19 -0400
Subject: [PATCH 4/4] BAEL-2760

---
 .../kotlin/com/baeldung/range/CustomColor.kt  | 56 +++++++++++++++++++
 .../com/baeldung/range/CustomColorTest.kt     | 41 ++++++++++++++
 2 files changed, 97 insertions(+)
 create mode 100644 core-kotlin-2/src/main/kotlin/com/baeldung/range/CustomColor.kt
 create mode 100644 core-kotlin-2/src/test/kotlin/com/baeldung/range/CustomColorTest.kt

diff --git a/core-kotlin-2/src/main/kotlin/com/baeldung/range/CustomColor.kt b/core-kotlin-2/src/main/kotlin/com/baeldung/range/CustomColor.kt
new file mode 100644
index 0000000000..b4fed13b18
--- /dev/null
+++ b/core-kotlin-2/src/main/kotlin/com/baeldung/range/CustomColor.kt
@@ -0,0 +1,56 @@
+package com.baeldung.range
+
+import java.lang.IllegalStateException
+
+class CustomColor(val rgb: Int): Comparable<CustomColor> {
+
+    override fun compareTo(other: CustomColor): Int {
+        return this.rgb.compareTo(other.rgb)
+    }
+
+    operator fun rangeTo(that: CustomColor) = ColorRange(this,that)
+
+    operator fun inc(): CustomColor {
+        return CustomColor(rgb + 1)
+    }
+
+    init {
+        if(rgb < 0x000000 || rgb > 0xFFFFFF){
+            throw IllegalStateException("RGB must be between 0 and 16777215")
+        }
+    }
+
+    override fun toString(): String {
+        return "CustomColor(rgb=$rgb)"
+    }
+}
+class ColorRange(override val start: CustomColor,
+                override val endInclusive: CustomColor) : ClosedRange<CustomColor>, Iterable<CustomColor>{
+
+    override fun iterator(): Iterator<CustomColor> {
+        return ColorIterator(start, endInclusive)
+    }
+}
+
+class ColorIterator(val start: CustomColor, val endInclusive: CustomColor) : Iterator<CustomColor> {
+
+    var initValue = start
+
+    override fun hasNext(): Boolean {
+        return initValue <= endInclusive
+    }
+
+    override fun next(): CustomColor {
+        return initValue++
+    }
+}
+
+fun main(args: Array<String>) {
+    val a = CustomColor(0xABCDEF)
+    val b = CustomColor(-1)
+    val c = CustomColor(0xABCDFF)
+
+    for(color in a..c){
+        println(color)
+    }
+}
\ No newline at end of file
diff --git a/core-kotlin-2/src/test/kotlin/com/baeldung/range/CustomColorTest.kt b/core-kotlin-2/src/test/kotlin/com/baeldung/range/CustomColorTest.kt
new file mode 100644
index 0000000000..8c8795ac42
--- /dev/null
+++ b/core-kotlin-2/src/test/kotlin/com/baeldung/range/CustomColorTest.kt
@@ -0,0 +1,41 @@
+package com.baeldung.range
+
+import org.junit.Test
+import java.lang.IllegalStateException
+import kotlin.test.assertFailsWith
+import kotlin.test.assertTrue
+
+class CustomColorTest {
+
+    @Test
+    fun testInvalidConstructor(){
+        assertFailsWith(IllegalStateException::class){
+            CustomColor(-1)
+        }
+    }
+
+    @Test
+    fun assertHas10Colors(){
+        assertTrue {
+            val a = CustomColor(1)
+            val b = CustomColor(10)
+            val range = a..b
+            for(cc in range){
+                println(cc)
+            }
+            range.toList().size == 10
+        }
+    }
+
+    @Test
+    fun assertContains0xCCCCCC(){
+        assertTrue {
+            val a = CustomColor(0xBBBBBB)
+            val b = CustomColor(0xDDDDDD)
+            val range = a..b
+            range.contains(CustomColor(0xCCCCCC))
+        }
+    }
+
+}
+