问题描述
要声明一个空切片，大小不固定，这样做更好吗:
To declare an empty slice, with a non-fixed size,is it better to do:
mySlice1 := make([]int, 0)
或:
mySlice2 := []int{}
只是想知道哪个是正确的方法.
Just wondering which one is the correct way.
推荐答案
您给出的两个替代方案在语义上是相同的，但是使用 make([]int, 0) 将导致内部调用runtime.makeslice(Go 1.16).
The two alternative you gave are semantically identical, but using make([]int, 0) will result in an internal call to runtime.makeslice (Go 1.16).
您还可以选择将其保留为 nil 值:
You also have the option to leave it with a nil value:
var myslice []int
如 Golang.org 博客中所述:
nil 切片在功能上等同于零长度切片，即使它不指向任何内容.它的长度为零，可以附加到分配中.
nil 切片将 json.Marshal() 转换为 "null" 而空切片将编组为 "[]"，正如@farwayer 指出的那样.
A nil slice will however json.Marshal() into "null" whereas an empty slice will marshal into "[]", as pointed out by @farwayer.
正如@ArmanOrdookhani 所指出的，上述选项都不会导致任何分配.
None of the above options will cause any allocation, as pointed out by @ArmanOrdookhani.
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