如何使用一个字节的缓冲区作为映射的密钥存储？

How use one byte buffer as key storage for map without copy?

func TestMap(t *testing.T) {
    testMap := make(map[string]int)

    //byteKey := make([]byte, 2)
    //byteKey[0] = 0
    byteKey := make([]byte, 1)

    {
        byteKey[0] = 'a'
        key := BytesToString(byteKey)
        testMap[key] += 1
    }

    {
        byteKey[0] = 'b'
        key := BytesToString(byteKey)
        testMap[key] += 1
    }

    {
        byteKey[0] = 'c'
        key := BytesToString(byteKey)
        testMap[key] += 1
    }

    for key, _ := range testMap {
        println(key, testMap[key])
    }
}

If BytesToString is just string cast ( string(buffer) ), that method print:

a 1 b 1 c 1

but if BytesToString has content:

func BytesToString(b []byte) string {
    bytesHeader := (*reflect.SliceHeader)(unsafe.Pointer(&b))
    strHeader := reflect.StringHeader{Data: bytesHeader.Data, Len: bytesHeader.Len}
    return *(*string)(unsafe.Pointer(&strHeader))
}

Result of function:

c 1 c 1 c 1

How use [a] ... byte [slice] ... as key ... for map?

You cannot. The language forbids slices as map keys as the content of a slice may change underhand (which is a property no map key must have).