YanoLab.LT 04での発表資料

1. tama @ YanoLab.LT

2. Go?

3. Big names!
Robert C Pike Plan 9
Kenneth Thompson Unix
Robert Griesemer V8, HotSpot
etc... Plan 9, GCC, etc...

4. Overviews
• Launched by Google
• R.I.P Noop?
• System Programming
• Server side?
• Frustration with existing languages
• Implement some useful ideas

5. Go!

6. Hello, World!
package main
import "fmt"
func main()
{
fmt.Printf("Hello, n")
}

7. Interface
• Duck typing
• Method set
• Not Java like interface
• Flexible!
• Add method to struct

8. e.g. Interface
// Apply this to any type implementing Sortable
func Sort(data Sortable)
{
for i := 1; i < data.Len(); i++ {
for j := i; j > 0 && data.Less(j, j-1); j-- {
data.Swap(j, j-1);
}
}
}

9. type Sortable interface
{
Len() int;
Less(i, j int) bool;
Swap(i, j int);
}
type Array []int
func (p Array) Len() int { return len(p); }
func (p Array) Less(i, j int) bool { return p[i] < p[j]; }
func (p Array) Swap(i, j int) { p[i], p[j] = p[j], p[i]; }

10. Goroutine
• Lightweight process
• go keyword
• Concurrently
• Channel (CSP)
• Communication between goroutines

11. e.g. Goroutine
func main()
{
ch := make(chan int); // Create a new channel.
go generate(ch); // Start as a goroutine.
for {
// do something
// fmt.Print(<-ch);
}
}

12. e.g. Channel
// Send the sequence 2, 3, 4, ... to channel 'ch'.
func generate(ch chan int)
{
for i := 2; ; i++ {
ch <- i // Send 'i' to channel 'ch'.
}
}

13. Others
• Garbage Collected
• M&S, IBM’s Recycler in the future
• Windows support
• Patch welcome! but...
• Multiple values
• etc...

14. Earthquake Problem
Issue 9

15. is here to stay!
• Future works
• Performance, Libraries, Tools, etc...
• Go vs Go!
• Going : Go is not Go!
• Issue9
• http://issuenine.com/ :)