What does `new` do in Go

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Note

new(Type) is the same as &Type{}

new command allocates memory, returns the memory address (meaning pointer)
- it only allocates memory, that’s all it does
- there’s more to variable declaration and initialization than memory allocation
the below code doesn’t work, throwing index out of range error
- the length of mySlice is 0
- because new allocates memories for []int, which has length 0!

mySlice := new([]int)
(*mySlice)[1] = 1  // panic: runtime error: index out of range [1] with length 0

mySlice := new([3]int)
(*mySlice)[1] = 1  // print out *mySlice is [1 0 0]