Go: using a pointer to array

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下面的不是指针指向数组，而是指针指向Slice

I‘m having a little play with google‘s Go language, and I‘ve run into something which is fairly basic in C but doesn‘t seem to be covered in the documentation I‘ve seen so far.

When I pass a pointer to an array to a function, I presumed we‘d have some way to access it as follows:

func conv(x []int, xlen int, h []int, hlen int, y *[]int)

    for i := 0; i<xlen; i++ {
        for j := 0; j<hlen; j++ {
            *y[i+j] += x[i]*h[j]
        }
    }
 }

But the Go compiler doesn‘t like this:

sean@spray:~/dev$ 8g broke.go
broke.go:8: invalid operation: y[i + j] (index of type *[]int)

Fair enough - it was just a guess. I have got a fairly straightforward workaround:

func conv(x []int, xlen int, h []int, hlen int, y_ *[]int) {
    y := *y_

    for i := 0; i<xlen; i++ {
        for j := 0; j<hlen; j++ {
            y[i+j] += x[i]*h[j]
        }
    }
}

But surely there‘s a better way. The annoying thing is that googling for info on Go isn‘t very useful as all sorts of C\C++\unrelated results appear for most search terms.

下面是解决方案：

the semicolon and the asterisk are added and removed.

*y[i+j] += x[i]*h[j]
-->
(*y)[i+j] += x[i] * h[j];

Go: using a pointer to array

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原文地址：http://www.cnblogs.com/ghgyj/p/4055410.html