Golang - 常用函数 - 持续更新

类型转换

int 型转换为 int8

func Uint8FromInt(n int) (uint8, error) {
	if 0 <= n && n <= math.MaxUint8 { // conversion is safe
		return uint8(n), nil
	}
	return 0, fmt.Errorf("%d is out of the uint8 range", n)
}

float64 转换为 int

func IntFromFloat64(x float64) int {
	if math.MinInt32 <= x && x <= math.MaxInt32 { // x lies in the integer range
		whole, fraction := math.Modf(x)
		if fraction >= 0.5 {
			whole++
		}
		return int(whole)
	}

	panic(fmt.Sprintf("%g is out of the int32 range", x))
}

量级定义

type ByteSize float64

const (
	_           = iota // 通过赋值给空白标识符来忽略值
	KB ByteSize = 1 << (10 * iota)
	MB
	GB
	TB
	PB
	EB
	ZB
	YB
)