Control Flow

Go provides a small, powerful set of control flow statements: if/else, switch, for, and defer. Unlike many languages, Go has only one loop construct — the for loop — which covers all looping patterns.

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If / Else

Basic If

if x > 10 {
    fmt.Println("x is greater than 10")
}

Note: no parentheses around the condition, but braces are required.

If / Else

if x > 10 {
    fmt.Println("big")
} else if x > 5 {
    fmt.Println("medium")
} else {
    fmt.Println("small")
}

If with Init Statement

Go allows a short statement before the condition — perfect for error handling:

if err := doSomething(); err != nil {
    fmt.Println("Error:", err)
    return
}
// err is not accessible here — scoped to the if block

This pattern is extremely common in Go. The variable declared in the init statement is scoped to the if/else block.

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Switch

Go's switch is more powerful than in many other languages:

Basic Switch

switch day {
case "Monday":
    fmt.Println("Start of the week")
case "Friday":
    fmt.Println("Almost weekend")
case "Saturday", "Sunday":
    fmt.Println("Weekend!")
default:
    fmt.Println("Midweek")
}

Key Differences from C/Java