Golang 関数のドキュメントでよくあるエラーは何ですか?

func Foo(x, y int)

//! Foo computes the sum of two integers.
func Foo(x, y int) int

// Foo computes the sum of two integers x and y.
func Foo(x, y int) int

// Foo computes the sum of two integers x and y.

func Foo(x, y int) int {
    return x + y
}

// Foo computes the sum of two integers.
func Foo(x, y int) int {
    return x + y
}

// Foo computes the sum of two integers.
func Foo(x, y int) int

// Examples of how to use Foo:
var (
    a = Foo(1, 2) // a == 3
    b = Foo(3, 4) // b == 7
)

type Point struct {
    X, Y int
}

// Sum returns the sum of the coordinates of two points.
func Sum(p1, p2 Point) (sumX, sumY int) {
    return p1.X + p2.X, p1.Y + p2.Y
}

// Example usage:
func main() {
    point1 := Point{1, 2}
    point2 := Point{3, 4}
    sumX, sumY := Sum(point1, point2)
    fmt.Printf("Sum of Point1 and Point2: (%d, %d)\n", sumX, sumY)
}