Example
- Typed collections
- Similar declaraction syntax
- Bunch of associated functions
// Unlike arrays, slices are typed only by the elements they contain (not the // number of elements). To create an empty slice with non-zero length, use the // builtin make. Here we make a slice of strings of length 3 (initially // zero-valued). s := make([]string, 3) fmt.Println("emp:", s) // We can set and get just like with arrays. s[0] = "a" s[1] = "b" s[2] = "c" fmt.Println("set:", s) fmt.Println("get:", s[2]) // len returns the length of the slice as expected. fmt.Println("len:", len(s)) // In addition to these basic operations, slices support several more that // make them richer than arrays. One is the builtin append, which returns a // slice containing one or more new values. Note that we need to accept a // return value from append as we may get a new slice value. s = append(s, "d") s = append(s, "e", "f") fmt.Println("apd:", s) // Slices can also be copy’d. Here we create an empty slice c of the same // length as s and copy into c from s. c := make([]string, len(s)) copy(c, s) fmt.Println("cpy:", c) // Slices support a “slice” operator with the syntax slice[low:high]. For // example, this gets a slice of the elements s[2], s[3], and s[4]. l := s[2:5] fmt.Println("sl1:", l) // This slices up to (but excluding) s[5]. l = s[:5] fmt.Println("sl2:", l) // And this slices up from (and including) s[2]. l = s[2:] fmt.Println("sl3:", l) // We can declare and initialize a variable for slice in a single line as well. t := []string{"g", "h", "i"} fmt.Println("dcl:", t) // Slices can be composed into multi-dimensional data structures. The length // of the inner slices can vary, unlike with multi-dimensional arrays. twoD := make([][]int, 3) for i := 0; i < 3; i++ { innerLen := i + 1 twoD[i] = make([]int, innerLen) for j := 0; j < innerLen; j++ { twoD[i][j] = i + j } } fmt.Println("2d: ", twoD)
emp: [ ] set: [a b c] get: c len: 3 apd: [a b c d e f] cpy: [a b c d e f] sl1: sl2: [a b c d e] sl3: dcl: [g h i] 2d: [[0] [1 2] [2 3 4]]