Constant Overflows Type

Why This Happens

Go constants are checked at compile time for overflow. If you assign a value that exceeds the range of the target type (for example, 256 into a uint8 which holds 0-255), the compiler rejects it. This prevents silent truncation bugs.

The Problem

func main() {
    var b uint8 = 256 // constant 256 overflows uint8
    fmt.Println(b)
}

The Fix

func main() {
    var b uint16 = 256
    fmt.Println(b)
}

Step-by-Step Fix

1. 1

   Identify the overflow

   Read the error to see which constant exceeds which type's range.

2. 2

   Choose a larger type

   Use uint16, int32, int64, or another type with sufficient range.

3. 3

   Check all related code

   Ensure the larger type is compatible with other code that uses this variable.