go - Bodiless function in Golang

Question

Reading the source code of math/floor.go, starting from line 13, I read some code like this:

func Floor(x float64) float64

func floor(x float64) float64 {
    if x == 0 || IsNaN(x) || IsInf(x, 0) {
        return x
    }
    if x < 0 {
        d, fract := Modf(-x)
        if fract != 0.0 {
            d = d + 1
        }
        return -d
    }
    d, _ := Modf(x)
    return d
}

It seems the func Floor has no body. I tried to copy and paste these code in my go file. it doesn't compile. The error message is missing function body. So my question is: is a bodiless function legal in Go's syntax? Thanks.

Answer 1

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