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SKILL JOURNEY

Kotlin

Modern JVM language

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Hello, World
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CHAPTER 01
Foundations
Lay the groundwork
0/5
1YOU ARE HERE
Lesson 1+70 XP
Hello, World
fun main.
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2
Lesson 2+60 XP
Val Constant
Immutable.
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3
Lesson 3+60 XP
Var
Mutable.
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4
Lesson 4+70 XP
Type
Annotation.
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5
Lesson 5+80 XP
String Template
Dollar sign.
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CHAPTER 02
Core Concepts
Build the core skills
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6
Lesson 6+100 XP
If Expression
Returns a value.
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7
Lesson 7+110 XP
Function
fun keyword.
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8
Lesson 8+100 XP
Nullable
? for nullable.
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9
Lesson 9+110 XP
Safe Call
?. operator.
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10
Lesson 10+80 XP
List
listOf.
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CHAPTER 03
Building Blocks
Wire things together
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11
Lesson 11+100 XP
Map
mapOf.
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12
Lesson 12+90 XP
For In
Iterate.
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13
Lesson 13+130 XP
Data Class
Auto equals/hashCode.
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14
Lesson 14+120 XP
When
Like switch.
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15
Lesson 15+120 XP
When Expression
Returns a value.
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CHAPTER 04
Advanced Patterns
Level up your craft
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Lesson 16+100 XP
Elvis
?: fallback.
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Lesson 17+110 XP
Lambda
Trailing lambda.
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18
Lesson 18+130 XP
Companion Object
Like static.
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19
Lesson 19+120 XP
Sealed Class
Closed hierarchy.
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Kotlin Master
19 lessons left to claim the crown