fix: coding style and file format for all example.

eBook/examples/chapter_6/function_literal.go

@@ -1,15 +1,16 @@
-package main
-import "fmt"
-
-func main() {
-	f()
-}
-
-func f() {
-	for i := 0; i < 4; i++ {
-		g := func(i int) { fmt.Printf("%d ", i) }
-		g(i)
-		fmt.Printf(" - g is of type %T and has value %v\n", g, g)
-	}
-	
-}
+package main
+
+import "fmt"
+
+func main() {
+	f()
+}
+
+func f() {
+	for i := 0; i < 4; i++ {
+		g := func(i int) { fmt.Printf("%d ", i) }
+		g(i)
+		fmt.Printf(" - g is of type %T and has value %v\n", g, g)
+	}
+
+}