Kotlin, At a Glance (Interview Preparation) : Part-I => Basic types

This is useful for people who has basic knowledge of Kotlin but want to revise concepts in a glance. This series will not have any code, but will help you to revise concepts. Hope you will enjoy this journey.

Basic Types

• Numbers : Double, Float, Long, Int, Short, Byte
• Literals: Decimals, Hexadecimals, Binary
• Underscores allowed to make literals more readable
• Only Explicit conversion are allowed to widen numbers
• Numbers or booleans are treated as JVM primitive type i.e. it will be boxed only if nullable reference used
• Internally, arithmetic Operations are performed using Operator overloading
• Characters: char => cannot be directly replaced by or as numbers
• Booleans: true/false value
• Arrays: It is a class which uses [ ] operator overloading to create array. Arrays can have initial value for each element, it can be even null initialised. Kotlin has special primitive type arrays as IntArray, ShortArray etc.
• Unsigned Integers: types are UByte, UShort, UInt, ULong
• Unsigned literals: can be written as 1u or 1U
• Strings: Immutable, Elements are characters to be accessed by index. + is used for concatenation.
• String literals: Escaped strings and Raw string (“”” Raw “””). Raw string uses trim margin function with default | (pipe) or any other character.
• String template: It can have simple name as $name or an expression as {$str.length}. It can be used in both escaped and raw strings.