Kotlin Expressions, Statements and Blocks

In this article, you will learn about Kotlin expressions, Kotlin statements, the difference between expressions and statements in Kotlin, and Kotlin blocks.

Kotlin expression

An expression is calculated to be a single value.Variables,Operatorsconstitute.

Let's take an example

val score: Int
score =　90　+　25

Here　 90 + 25is an expression that returns an Int value.

In Kotlin, if is an expression, unlike Java (in Java, if is a statement). For example

fun　main(args:　Array<String>)　{
　　　　val a =　12
　　　　val b =　13
　　　　val max: Int
　　　　max = if (a > b) a else b
　　　　println("$max")
}

Here, if (a > b) a else b is an expression. Then the value of the expression is assigned to the max variable in the above program.

Kotlin statement

A statement is all the content that makes up a complete execution unit. For example,

val score =　90　+　25

Here,90 + 25 is a return115The expression, and val score = 9*5; is a statement.

An expression is a part of a statement.

Some examples:

println("Howdy")

var a =　5
++a

max = if (a > b) a else b

Kotlin block

A block is a group of statements (zero or more) enclosed in curly braces { }. For example,

fun　main(args:　Array<String>)　{　　//　main function block
　　　　val　flag　=　true
　　　　if　(flag　==　true)　{　　　　　　//Start of if block
　　　　　　　　print("Hey　")
　　　　　　　　print("jude!")
　　　　}　　　　　　　　　　　　　　　　　　　　　　　　//End of if block
}　　　　　　　　　　　　　　　　　　　　　　　　　　　　//　End of main function block

These are two statements inside the if branch block: print("Hey ") and print(" jude!").

print("Hey　")
print("jude!")

Similarly, the main() function also has a block body.

val　flag　=　true
if　(flag　==　true)　{　　　　　　//Start Block
　　　　print("Hey　")
　　　　print("jude!")
}　　　　　　　　　　　　　　　　　　　　　　　　//End Block