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What is the meaning of "... Type" in the Golang

this code is in builti.go

// The append built-in function appends elements to the end of a slice. If
// it has sufficient capacity, the destination is resliced to accommodate the
// new elements. If it does not, a new underlying array will be allocated.
// Append returns the updated slice. It is therefore necessary to store the
// result of append, often in the variable holding the slice itself:
//  slice = append(slice, elem1, elem2)
//  slice = append(slice, anotherSlice...)
// As a special case, it is legal to append a string to a byte slice, like this:
//  slice = append([]byte("hello "), "world"...)
func append(slice []Type, elems ...Type) []Type

the last line made me feel very confused. I do not know the meaning ...Type.

these are other codes.

package main

import "fmt"

func main() {
   s := []int{1,2,3,4,5}
   s1 := s[:2]
   s2 := s[2:]
   s3 := append(s1, s2...)
   fmt.Println(s1, s2, s3)

}

result

[1 2] [3 4 5] [1 2 3 4 5]

I assume that the function ...is to select all the elements from the elem.

I can not find an official explanation

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1 answer

The code in builtin.go serves as documentation. Code not compiled.

...indicates that the final parameter of the function is variable. Variadic parameters - documented in the Go Language specification .

The Type part is backup for any type of Go.

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