Исходники и презентации

lessons/slices_and_arrays/append_implementation/main.go

@@ -0,0 +1,39 @@
+package main
+
+import "fmt"
+
+func Append(slice []int, data ...int) []int {
+	previousLength := len(slice)
+	newLength := previousLength + len(data)
+
+	if newLength > cap(slice) {
+		// without smart growth for big slices
+		capacity := previousLength * 2
+		if capacity == 0 {
+			capacity = 1
+		}
+
+		newSlice := make([]int, capacity)
+		copy(newSlice, slice)
+		slice = newSlice
+	}
+
+	slice = slice[:newLength]
+	copy(slice[previousLength:newLength], data)
+	return slice
+}
+
+func main() {
+	data := []int{}
+	data = append(data, 1)
+	data = append(data, 2)
+	data = append(data, 3)
+	data = append(data, 4)
+	data = append(data, 5)
+	data = append(data, 6)
+	data = append(data, 7)
+	data = append(data, 8)
+	data = append(data, 9)
+
+	fmt.Println(data, len(data), cap(data))
+}