The document discusses loops and iteration in Google Go. It covers for loops, infinite loops, the range keyword, functions, closures, and type assertions. Code examples are provided to demonstrate conditional loops, printing slice elements with a for loop and range, passing slices to functions, asserting the type within a function, and using closures to pass a slice to a function.

1. going loopy
adventures in iteration with google go
@feyeleanor
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2. the task
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3. 0: 0
1: 2
2: 4
3: 6
4: 8
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4. the conditional loop
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5. package main
import "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
fmt.Printf("%v: %vn", i, s[i])
}
}
Going Loopy http://slides.games-with-brains.net/5

6. package main
import "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
fmt.Printf("%v: %vn", i, s[i])
}
}
Going Loopy http://slides.games-with-brains.net/6

7. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
7Going Loopy http://slides.games-with-brains.net/

8. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
8Going Loopy http://slides.games-with-brains.net/

9. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
9Going Loopy http://slides.games-with-brains.net/

10. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
Going Loopy http://slides.games-with-brains.net/10

11. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
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12. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
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13. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
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14. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
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15. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
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16. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
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17. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
17Going Loopy http://slides.games-with-brains.net/

18. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
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19. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
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20. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
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21. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i := 0; i < len(s); i++ {
Printf("%v: %vn", i, s[i])
}
}
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22. the infinite loop
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23. package main
import . "fmt"
func main() {
defer func() {
recover()
}()
s := []int{0, 2, 4, 6, 8}
i := 0
for {
Printf("%v: %vn", i, s[i])
i++
}
}
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24. package main
import . "fmt"
func main() {
defer func() {
recover()
}()
s := []int{0, 2, 4, 6, 8}
i := 0
for {
Printf("%v: %vn", i, s[i])
i++
}
}
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25. package main
import . "fmt"
func main() {
defer func() {
recover()
}()
s := []int{0, 2, 4, 6, 8}
i := 0
for {
Printf("%v: %vn", i, s[i])
i++
}
}
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26. package main
import . "fmt"
func main() {
defer func() {
recover()
}()
s := []int{0, 2, 4, 6, 8}
i := 0
for {
Printf("%v: %vn", i, s[i])
i++
}
}
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27. package main
import . "fmt"
func main() {
defer func() {
recover()
}()
s := []int{0, 2, 4, 6, 8}
i := 0
for {
Printf("%v: %vn", i, s[i])
i++
}
}
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28. package main
import . "fmt"
func main() {
defer func() {
recover()
}()
s := []int{0, 2, 4, 6, 8}
i := 0
for i := 0; ; i++ {
Printf("%v: %vn", i, s[i])
i++
}
}
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29. the range
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30. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
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31. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
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32. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
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33. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
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34. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
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35. a functional interlude
35Going Loopy http://slides.games-with-brains.net/

36. package main
import . "fmt"
func main() {
print_slice([]int{0, 2, 4, 6, 8})
}
func print_slice(s []int) {
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
36Going Loopy http://slides.games-with-brains.net/

37. package main
import . "fmt"
func main() {
print_slice([]int{0, 2, 4, 6, 8})
}
func print_slice(s []int) {
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
37Going Loopy http://slides.games-with-brains.net/

38. package main
import . "fmt"
func main() {
print_slice([]int{0, 2, 4, 6, 8})
}
func print_slice(s []int) {
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
38Going Loopy http://slides.games-with-brains.net/

39. package main
import . "fmt"
func main() {
print_slice(0, 2, 4, 6, 8)
}
func print_slice(s ...int) {
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
39Going Loopy http://slides.games-with-brains.net/

40. asserting type
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41. package main
import . "fmt"
func main() {
print_slice([]int{0, 2, 4, 6, 8})
}
func print_slice(s interface{}) {
for i, v := range s.([]int) {
Printf("%v: %vn", i, v)
}
}
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42. package main
import . "fmt"
func main() {
print_slice([]int{0, 2, 4, 6, 8})
}
func print_slice(s interface{}) {
for i, v := range s.([]int) {
Printf("%v: %vn", i, v)
}
}
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43. package main
import . "fmt"
func main() {
print_slice([]int{0, 2, 4, 6, 8})
}
func print_slice(s interface{}) {
if s, ok := s.([]int); ok {
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
}
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44. package main
import . "fmt"
func main() {
print_slice([]int{0, 2, 4, 6, 8})
}
func print_slice(s interface{}) {
if s, ok := s.([]int); ok {
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
}
Going Loopy http://slides.games-with-brains.net/44

45. package main
import . "fmt"
func main() {
print_slice([]int{0, 2, 4, 6, 8})
}
func print_slice(s interface{}) {
if s, ok := s.([]int); ok {
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
}
Going Loopy http://slides.games-with-brains.net/45

46. package main
import . "fmt"
func main() {
print_slice([]int{0, 2, 4, 6, 8})
}
func print_slice(s interface{}) {
if s, ok := s.([]int); ok {
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
}
Going Loopy http://slides.games-with-brains.net/46

47. package main
import . "fmt"
func main() {
print_slice([]int{0, 2, 4, 6, 8})
}
func print_slice(s interface{}) {
switch s := s.(type) {
case []int:
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
}
Going Loopy http://slides.games-with-brains.net/47

48. package main
import . "fmt"
func main() {
print_slice([]int{0, 2, 4, 6, 8})
}
func print_slice(s interface{}) {
switch s := s.(type) {
case []int:
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
}
Going Loopy http://slides.games-with-brains.net/48

49. package main
import . "fmt"
func main() {
print_slice([]int{0, 2, 4, 6, 8})
}
func print_slice(s interface{}) {
switch s := s.(type) {
case []int:
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
}
Going Loopy http://slides.games-with-brains.net/49

50. closures
50Going Loopy http://slides.games-with-brains.net/

51. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
print_slice(func(i int) int { return s[i] })
}
func print_slice(s interface{}) {
switch s := s.(type) {
case func(int) int:
for i := 0; i < 5; i++ {
Printf("%v: %vn", i, s(i))
}
}
}
51Going Loopy http://slides.games-with-brains.net/

52. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
print_slice(func(i int) int { return s[i] })
}
func print_slice(s interface{}) {
switch s := s.(type) {
case func(int) int:
for i := 0; i < 5; i++ {
Printf("%v: %vn", i, s(i))
}
}
}
52Going Loopy http://slides.games-with-brains.net/

53. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
print_slice(func(i int) int { return s[i] })
}
func print_slice(s interface{}) {
switch s := s.(type) {
case func(int) int:
for i := 0; i < 5; i++ {
Printf("%v: %vn", i, s(i))
}
}
}
53Going Loopy http://slides.games-with-brains.net/

54. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
print_slice(func(i int) int { return s[i] })
}
func print_slice(s interface{}) {
switch s := s.(type) {
case func(int) int:
for i := 0; i < 5; i++ {
Printf("%v: %vn", i, s(i))
}
}
}
54Going Loopy http://slides.games-with-brains.net/

55. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
print_slice(func(i int) int { return s[i] })
}
func print_slice(s interface{}) {
switch s := s.(type) {
case func(int) int:
for i := 0; i < 5; i++ {
Printf("%v: %vn", i, s(i))
}
}
}
55Going Loopy http://slides.games-with-brains.net/

56. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
print_slice(func(i int) int { return s[i] })
}
func print_slice(s interface{}) {
switch s := s.(type) {
case func(int) int:
for i := 0; i < 5; i++ {
Printf("%v: %vn", i, s(i))
}
}
}
56Going Loopy http://slides.games-with-brains.net/

57. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
print_slice(func(i int) int { return s[i] })
}
func print_slice(s interface{}) {
switch s := s.(type) {
case func(int) int:
for i := 0; i < 5; i++ {
Printf("%v: %vn", i, s(i))
}
}
}
57Going Loopy http://slides.games-with-brains.net/

58. channels
58Going Loopy http://slides.games-with-brains.net/

59. package main
import . "fmt"
func main() {
c := make(chan int)
go func() {
for _, v := range []int{0, 2, 4, 6, 8} {
c <- v
}
close(c)
}()
Printf("elements: %vn", print_channel(c))
}
func print_channel(c chan int) (i int) {
for v := range c {
Printf("%v: %vn", i, v)
i++
}
return
}
59Going Loopy http://slides.games-with-brains.net/

60. package main
import . "fmt"
func main() {
c := make(chan int, 16)
go func() {
for _, v := range []int{0, 2, 4, 6, 8} {
c <- v
}
close(c)
}()
Printf("elements: %vn", print_channel(c))
}
func print_channel(c chan int) (i int) {
for v := range c {
Printf("%v: %vn", i, v)
i++
}
return
}
60Going Loopy http://slides.games-with-brains.net/

61. package main
import . "fmt"
func main() {
c := make(chan int)
go func() {
for _, v := range []int{0, 2, 4, 6, 8} {
c <- v
}
close(c)
}()
Printf("elements: %vn", print_channel(c))
}
func print_channel(c chan int) (i int) {
for v := range c {
Printf("%v: %vn", i, v)
i++
}
return
}
61Going Loopy http://slides.games-with-brains.net/

62. package main
import . "fmt"
func main() {
c := make(chan int)
go func() {
for _, v := range []int{0, 2, 4, 6, 8} {
c <- v
}
close(c)
}()
Printf("elements: %vn", print_channel(c))
}
func print_channel(c chan int) (i int) {
for v := range c {
Printf("%v: %vn", i, v)
i++
}
return
}
62Going Loopy http://slides.games-with-brains.net/

63. package main
import . "fmt"
func main() {
c := make(chan int)
go func() {
for _, v := range []int{0, 2, 4, 6, 8} {
c <- v
}
close(c)
}()
Printf("elements: %vn", print_channel(c))
}
func print_channel(c chan int) (i int) {
for v := range c {
Printf("%v: %vn", i, v)
i++
}
return
}
63Going Loopy http://slides.games-with-brains.net/

64. package main
import . "fmt"
func main() {
c := make(chan int)
go func() {
for _, v := range []int{0, 2, 4, 6, 8} {
c <- v
}
close(c)
}()
Printf("elements: %vn", print_channel(c))
}
func print_channel(c chan int) (i int) {
for v := range c {
Printf("%v: %vn", i, v)
i++
}
return
}
64Going Loopy http://slides.games-with-brains.net/

65. package main
import . "fmt"
func main() {
c := make(chan int)
go func() {
for _, v := range []int{0, 2, 4, 6, 8} {
c <- v
}
close(c)
}()
Printf("elements: %vn", print_channel(c))
}
func print_channel(c chan int) (i int) {
for v := range c {
Printf("%v: %vn", i, v)
i++
}
return
}
65Going Loopy http://slides.games-with-brains.net/

66. package main
import . "fmt"
func main() {
c := make(chan int)
go func() {
for _, v := range []int{0, 2, 4, 6, 8} {
c <- v
}
close(c)
}()
Printf("elements: %vn", print_channel(c))
}
func print_channel(c chan int) (i int) {
for v := range c {
Printf("%v: %vn", i, v)
i++
}
return
}
66Going Loopy http://slides.games-with-brains.net/

67. package main
import . "fmt"
func main() {
c := make(chan int)
go func() {
for _, v := range []int{0, 2, 4, 6, 8} {
c <- v
}
close(c)
}()
Printf("elements: %vn", print_channel(c))
}
func print_channel(c chan int) (i int) {
for v := range c {
Printf("%v: %vn", i, v)
i++
}
return
}
67Going Loopy http://slides.games-with-brains.net/

68. upon reflection
68Going Loopy http://slides.games-with-brains.net/

69. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := s.(type) {
case func(int) int:
for i := 0; i < 5; i++ {
Printf("%v: %vn", i, s(i))
}
case []int:
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
}
69Going Loopy http://slides.games-with-brains.net/

70. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := s.(type) {
case func(int) int:
for i := 0; i < 5; i++ {
Printf("%v: %vn", i, s(i))
}
case []int:
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
}
70Going Loopy http://slides.games-with-brains.net/

71. package main
import . "fmt"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := s.(type) {
case func(int) int:
for i := 0; i < 5; i++ {
Printf("%v: %vn", i, s(i))
}
case []int:
for i, v := range s {
Printf("%v: %vn", i, v)
}
}
}
71Going Loopy http://slides.games-with-brains.net/

72. package main
import . "fmt"
import "reflect"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := reflect.ValueOf(s); s.Kind() {
case reflect.Func:
for i := 0; i < 5; i++ {
p := []reflect.Value{ reflect.ValueOf(i) }
Printf("%v: %vn", i, s.Call(p)[0].Interface{})
}
case reflect.Slice:
for i := 0; i < s.Len(); i++ {
Printf("%v: %vn", i, s.Index(i))
}
}
}
72Going Loopy http://slides.games-with-brains.net/

73. package main
import . "fmt"
import "reflect"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := reflect.ValueOf(s); s.Kind() {
case reflect.Func:
for i := 0; i < 5; i++ {
p := []reflect.Value{ reflect.ValueOf(i) }
Printf("%v: %vn", i, s.Call(p)[0].Interface())
}
case reflect.Slice:
for i := 0; i < s.Len(); i++ {
Printf("%v: %vn", i, s.Index(i).Interface())
}
}
}
73Going Loopy http://slides.games-with-brains.net/

74. package main
import . "fmt"
import "reflect"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := reflect.ValueOf(s); s.Kind() {
case reflect.Func:
for i := 0; i < 5; i++ {
p := []reflect.Value{ reflect.ValueOf(i) }
Printf("%v: %vn", i, s.Call(p)[0].Interface())
}
case reflect.Slice:
for i := 0; i < s.Len(); i++ {
Printf("%v: %vn", i, s.Index(i).Interface())
}
}
}
74Going Loopy http://slides.games-with-brains.net/

75. package main
import . "fmt"
import "reflect"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := reflect.ValueOf(s); s.Kind() {
case reflect.Func:
for i := 0; i < 5; i++ {
p := []reflect.Value{ reflect.ValueOf(i) }
Printf("%v: %vn", i, s.Call(p)[0].Interface())
}
case reflect.Slice:
for i := 0; i < s.Len(); i++ {
Printf("%v: %vn", i, s.Index(i).Interface())
}
}
}
75Going Loopy http://slides.games-with-brains.net/

76. package main
import . "fmt"
import "reflect"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := reflect.ValueOf(s); s.Kind() {
case reflect.Func:
for i := 0; i < 5; i++ {
p := []reflect.Value{ reflect.ValueOf(i) }
Printf("%v: %vn", i, s.Call(p)[0].Interface())
}
case reflect.Slice:
for i := 0; i < s.Len(); i++ {
Printf("%v: %vn", i, s.Index(i).Interface())
}
}
}
76Going Loopy http://slides.games-with-brains.net/

77. package main
import . "fmt"
import . "reflect"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := ValueOf(s); s.Kind() {
case Func:
for i := 0; i < 5; i++ {
p := []Value{ ValueOf(i) }
Printf("%v: %vn", i, s.Call(p)[0].Interface())
}
case Slice:
for i := 0; i < s.Len(); i++ {
Printf("%v: %vn", i, s.Index(i).Interface())
}
}
}
77Going Loopy http://slides.games-with-brains.net/

78. package main
import . "fmt"
import . "reflect"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := ValueOf(s); s.Kind() {
case Func:
for i := 0; i < 5; i++ {
p := []Value{ ValueOf(i) }
Printf("%v: %vn", i, s.Call(p)[0].Interface())
}
case Slice:
for i := 0; i < s.Len(); i++ {
Printf("%v: %vn", i, s.Index(i).Interface())
}
}
}
78Going Loopy http://slides.games-with-brains.net/

79. package main
import . "fmt"
import . "reflect"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := ValueOf(s); s.Kind() {
case Func:
for i := 0; i < 5; i++ {
p := []Value{ ValueOf(i) }
Printf("%v: %vn", i, s.Call(p)[0].Interface())
}
case Slice:
for i := 0; i < s.Len(); i++ {
Printf("%v: %vn", i, s.Index(i).Interface())
}
}
}
79Going Loopy http://slides.games-with-brains.net/

80. package main
import . "fmt"
import . "reflect"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := ValueOf(s); s.Kind() {
case Func:
for i := 0; i < 5; i++ {
p := []Value{ ValueOf(i) }
Printf("%v: %vn", i, s.Call(p)[0].Interface())
}
case Slice:
for i := 0; i < s.Len(); i++ {
Printf("%v: %vn", i, s.Index(i).Interface())
}
}
}
80Going Loopy http://slides.games-with-brains.net/

81. package main
import . "fmt"
import . "reflect"
func main() {
s := []int{0, 2, 4, 6, 8}
print_values(s)
print_values(func(i int) int { return s[i] })
}
func print_values(s interface{}) {
switch s := ValueOf(s); s.Kind() {
case Func:
for i := 0; i < 5; i++ {
p := []Value{ ValueOf(i) }
Printf("%v: %vn", i, s.Call(p)[0].Interface())
}
case Slice:
for i := 0; i < s.Len(); i++ {
Printf("%v: %vn", i, s.Index(i).Interface())
}
}
}
81Going Loopy http://slides.games-with-brains.net/

82. user-defined type
82Going Loopy http://slides.games-with-brains.net/

83. package main
import . "fmt"
type IterableSlice []int
func (i IterableSlice) Each(f func(interface{})) {
for _, v := range i {
f(v)
}
}
func main() {
s := IterableSlice{ 0, 2, 4, 6, 8 }
i := 0
s.Each(func(v interface{}) {
Printf("%v: %vn", i, v)
i++
})
}
83Going Loopy http://slides.games-with-brains.net/

84. package main
import . "fmt"
type IterableSlice []int
func (i IterableSlice) Each(f func(interface{})) {
for _, v := range i {
f(v)
}
}
func main() {
s := IterableSlice{ 0, 2, 4, 6, 8 }
i := 0
s.Each(func(v interface{}) {
Printf("%v: %vn", i, v)
i++
})
}
84Going Loopy http://slides.games-with-brains.net/

85. package main
import . "fmt"
type IterableSlice []int
func (i IterableSlice) Each(f func(interface{})) {
for _, v := range i {
f(v)
}
}
func main() {
s := IterableSlice{ 0, 2, 4, 6, 8 }
i := 0
s.Each(func(v interface{}) {
Printf("%v: %vn", i, v)
i++
})
}
85Going Loopy http://slides.games-with-brains.net/

86. package main
import . "fmt"
type IterableSlice []int
func (i IterableSlice) Each(f func(interface{})) {
for _, v := range i {
f(v)
}
}
func main() {
s := IterableSlice{ 0, 2, 4, 6, 8 }
i := 0
s.Each(func(v interface{}) {
Printf("%v: %vn", i, v)
i++
})
}
86Going Loopy http://slides.games-with-brains.net/

87. package main
import . "fmt"
type IterableSlice []int
func (i IterableSlice) Each(f func(interface{})) {
for _, v := range i {
f(v)
}
}
func main() {
s := IterableSlice{ 0, 2, 4, 6, 8 }
i := 0
s.Each(func(v interface{}) {
Printf("%v: %vn", i, v)
i++
})
}
87Going Loopy http://slides.games-with-brains.net/

88. package main
import . "fmt"
type IterableSlice []int
func (i IterableSlice) Each(f func(interface{})) {
for _, v := range i {
f(v)
}
}
func main() {
s := IterableSlice{ 0, 2, 4, 6, 8 }
i := 0
s.Each(func(v interface{}) {
Printf("%v: %vn", i, v)
i++
})
}
88Going Loopy http://slides.games-with-brains.net/

89. package main
import . "fmt"
type IterableSlice []int
func (i IterableSlice) Each(f func(interface{})) {
for _, v := range i {
f(v)
}
}
func main() {
s := IterableSlice{ 0, 2, 4, 6, 8 }
i := 0
s.Each(func(v interface{}) {
Printf("%v: %vn", i, v)
i++
})
}
89Going Loopy http://slides.games-with-brains.net/

90. package main
import . "fmt"
type Iterable interface {
Each(func(interface{}))
}
type IterableSlice []int
func (i IterableSlice) Each(f func(interface{})) {
for _, v := range i {
f(v)
}
}
func main() {
var s Iterable = IterableSlice{ 0, 2, 4, 6, 8 }
i := 0
s.Each(func(v interface{}) {
Printf("%v: %vn", i, v)
i++
})
}
90Going Loopy http://slides.games-with-brains.net/

91. package main
import . "fmt"
type Iterable interface {
Each(func(interface{}))
}
type IterableSlice []int
func (i IterableSlice) Each(f func(interface{})) {
for _, v := range i {
f(v)
}
}
func main() {
var s Iterable = IterableSlice{ 0, 2, 4, 6, 8 }
i := 0
s.Each(func(v interface{}) {
Printf("%v: %vn", i, v)
i++
})
}
91Going Loopy http://slides.games-with-brains.net/

92. package main
import . "fmt"
type Iterable interface {
Each(func(interface{}))
}
type IterableSlice []int
func (i IterableSlice) Each(f func(interface{})) {
for _, v := range i {
f(v)
}
}
func main() {
var s Iterable = IterableSlice{ 0, 2, 4, 6, 8 }
i := 0
s.Each(func(v interface{}) {
Printf("%v: %vn", i, v)
i++
})
}
92Going Loopy http://slides.games-with-brains.net/

93. package main
import . "fmt"
type Iterable interface {
Each(func(interface{}))
}
type IterableSlice []int
func (i IterableSlice) Each(f func(interface{})) {
for _, v := range i {
f(v)
}
}
func main() {
var s Iterable = IterableSlice{ 0, 2, 4, 6, 8 }
i := 0
s.Each(func(v interface{}) {
Printf("%v: %vn", i, v)
i++
})
}
93Going Loopy http://slides.games-with-brains.net/

94. package main
import . "fmt"
type Iterable interface {
Each(func(interface{}))
}
type IterableLimit int
func (i IterableLimit) Each(f func(interface{})) {
for v := 0; v < i; v++ {
f(v)
}
}
func main() {
var s Iterable = IterableLimit(5)
i := 0
s.Each(func(v interface{}) {
Printf("%v: %vn", i, v)
i++
})
}
94Going Loopy http://slides.games-with-brains.net/

95. AND YES, I DO
HAVE A BOOK
IN THE WORKS
IF THAT'S
YOUR THING
leanpub://GoNotebook