Channelsのcloseとrange

sample1.go

package main

import (
  "fmt"
)

func fibonacci(n int, c chan int) {
  x, y := 0, 1

  for i := 0; i < n; i++ {
    c <- x
    x, y = y, x+y
  }

  close( c )
}

func main() {
  c := make( chan int, 10 )
  go fibonacci( cap( c ), c )

  for i := range c {
    fmt.Println( i )
  }
}

sample2.go

package main

import (
  "fmt"
  "time"
)

func fibonacci(n int, c chan int) {
  x, y := 0, 1

  for i := 0; i < n; i++ {
    c <- x
    x, y = y, x+y
  }

  close( c )
}

func main() {
  c := make( chan int, 10 )
  go fibonacci( cap( c ), c )

  i0, j0 := <- c
  fmt.Println( i0, j0 )
  i1, j1 := <- c
  fmt.Println( i1, j1 )
  i2, j2 := <- c
  fmt.Println( i2, j2 )
  i3, j3 := <- c
  fmt.Println( i3, j3 )
  i4, j4 := <- c
  fmt.Println( i4, j4 )
  i5, j5 := <- c
  fmt.Println( i5, j5 )
  i6, j6 := <- c
  fmt.Println( i6, j6 )
  i7, j7 := <- c
  fmt.Println( i7, j7 )
  i8, j8 := <- c
  fmt.Println( i8, j8 )
  i9, j9 := <- c
  fmt.Println( i9, j9 )
  i10, j10 := <- c
  fmt.Println( i10, j10 )
}