2.2. Flow control

If Else

Conditionals in Go are similiar to other programming languages. Notice that there are no round brackets surrounding the condition.

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package main

import "fmt"

func main() {
	x := 10
	if x >= 5 {
		fmt.Println("X is greater or equal to 5")
	} else {
		fmt.Println("X is smaller than 5")
	}
}

Output:
X is greater or equal to 5

Multiple logical conditions can be combined with && (AND) and || (OR).

Switch

If you are testing one variable for multiple conditions with else if the code can quickly become confusing. In these cases a switch statement can be used. The last default case is equivalent to else.

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package main

import (
	"fmt"
)

func main() {
	dayOfWeek := 3

	switch dayOfWeek {
	case 1:
		fmt.Println("Sunday")
	case 2:
		fmt.Println("Monday")
	case 3:
		fmt.Println("Tuesday")
	case 4:
		fmt.Println("Wednesday")
	case 5:
		fmt.Println("Thursday")
	case 6:
		fmt.Println("Friday")
	case 7:
		fmt.Println("Saturday")
	default:
		fmt.Println("Invalid day")
	}
}

Output:
Tuesday

Loops

The examples below show the basic loop constructs. We will look at an additional variant in the chapter 2.6. Slices.

For - Classical

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package main

import "fmt"

func main() {
	for i := 0; i < 5; i++ {
		fmt.Println(i)
	}
}

Output:
0
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4

While equivalent

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package main

import "fmt"

func main() {
	i := 0
	for i < 5 {
		fmt.Println(i)
		i++
	}
}

Output:
0
1
2
3
4

Last modified May 29, 2024: Merge pull request #205 from acend/renovate/actions-checkout-digest (cc47d9a)