23 lines
617 B
Go
23 lines
617 B
Go
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package main
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import (
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"fmt"
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"unsafe"
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)
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func main() {
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const elemSize = unsafe.Sizeof(int32(0)) // 4 bytes
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array := [...]int32{1, 2, 3}
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pointer := unsafe.Pointer(&array)
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first := *(*int32)(unsafe.Add(pointer, 0*elemSize)) // => data2[0]
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second := *(*int32)(unsafe.Add(pointer, 1*elemSize)) // => data2[1]
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third := *(*int32)(unsafe.Add(pointer, 2*elemSize)) // => data2[2]
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dangerous1 := *(*int32)(unsafe.Add(pointer, -1)) // => data2[-1]
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dangerous2 := *(*int32)(unsafe.Add(pointer, 3)) // => data2[3]
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fmt.Println("correct:", first, second, third)
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fmt.Println("dangeroues:", dangerous1, dangerous2)
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}
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