Just another update

Task/Substring/Go/substring-1.go

@@ -0,0 +1,26 @@
+package main
+
+import (
+    "fmt"
+    "strings"
+)
+
+func main() {
+    s := "ABCDEFGH"
+    n, m := 2, 3
+    // for reference
+    fmt.Println("Index: ", "01234567")
+    fmt.Println("String:", s)
+    // starting from n characters in and of m length
+    fmt.Printf("Start %d, length %d:    %s\n", n, m, s[n : n+m])
+    // starting from n characters in, up to the end of the string
+    fmt.Printf("Start %d, to end:      %s\n", n, s[n:])
+    // whole string minus last character
+    fmt.Printf("All but last:         %s\n", s[:len(s)-1])
+    // starting from a known character within the string and of m length
+    dx := strings.IndexByte(s, 'D')
+    fmt.Printf("Start 'D', length %d:  %s\n", m, s[dx : dx+m])
+    // starting from a known substring within the string and of m length
+    sx := strings.Index(s, "DE")
+    fmt.Printf(`Start "DE", length %d: %s`+"\n", m, s[sx : sx+m])
+}

Task/Substring/Go/substring-2.go

@@ -0,0 +1,29 @@
+package main
+
+import (
+    "fmt"
+    "strings"
+)
+
+func main() {
+    s := "αβγδεζηθ"
+    r := []rune(s)
+    n, m := 2, 3
+    kc := 'δ'  // known character
+    ks := "δε" // known string
+    // for reference
+    fmt.Println("Index: ", "01234567")
+    fmt.Println("String:", s)
+    // starting from n characters in and of m length
+    fmt.Printf("Start %d, length %d:    %s\n", n, m, string(r[n:n+m]))
+    // starting from n characters in, up to the end of the string
+    fmt.Printf("Start %d, to end:      %s\n", n, string(r[n:]))
+    // whole string minus last character
+    fmt.Printf("All but last:         %s\n", string(r[:len(r)-1]))
+    // starting from a known character within the string and of m length
+    dx := strings.IndexRune(s, kc)
+    fmt.Printf("Start %q, length %d:  %s\n", kc, m, string([]rune(s[dx:])[:m]))
+    // starting from a known substring within the string and of m length
+    sx := strings.Index(s, ks)
+    fmt.Printf("Start %q, length %d: %s\n", ks, m, string([]rune(s[sx:])[:m]))
+}

Task/Substring/Go/substring.go

@@ -1,14 +0,0 @@
-package main
-import "fmt"
-import "strings"
-
-func main() {
-  s := "ABCDEFGH"
-  n, m := 2, 3
-
-  fmt.Println(s[n:n+m]) // "CDE"
-  fmt.Println(s[n:]) // "CDEFGH"
-  fmt.Println(s[0:len(s)-1]) // "ABCDEFG"
-  fmt.Println(s[strings.Index(s, "D"):strings.Index(s, "D")+m]) // "DEF"
-  fmt.Println(s[strings.Index(s, "DE"):strings.Index(s, "DE")+m]) // "DEF"
-}