Golang walk through nested structures with formatted, indented output

nestedStructs.go

package main

import (
	"fmt"
	"reflect"
	"strings"
)

type S1 struct {
	A1 int
	B1 string
	S2
}

type S2 struct {
	A2 int64
	S3
	B2 complex64
}

type S3 struct {
	A3 string
	b3 bool
	C3 float64
}

func main() {

	s3 := S3{"Third", true, 3.1415926535}
	s2 := S2{4123456789, s3, -2 + 3i}
	s1 := S1{7, "first", s2}

	walkNestedStruct(s1, 0)
}

func walkNestedStruct(ns interface{}, level int) {
	nsVal := reflect.ValueOf(ns)
	nsType := nsVal.Type()

	for i := 0; i < nsVal.NumField(); i++ {
		f := nsVal.Field(i)

		// Skip unexported fields
		if !f.CanInterface() {
			continue
		}

		fmt.Printf("%s%s", strings.Repeat(" ", level), nsType.Field(i).Name)

		if f.Kind() == reflect.Struct {
			fmt.Println(" {")
			walkNestedStruct(f.Interface(), level+4)
			fmt.Printf("%s}\n", strings.Repeat(" ", level))
		} else {
			fmt.Printf(" %s = %v\n", f.Type(), f.Interface())
		}
	}
}