Go: How I learned to stop worrying and love the gopher

An introduction / overview of the Go programming language targeted at python developers who are curious about Go.

Transcript

1. Go Go How I learned to stop worrying and love the gopher
2. My background My background • Python • Web design / development • Not compiled languages
3. I know what you're thinking....
4. A new new language you say?
5. A new new language you say? cool story bro. cool story bro.
6. "Go is not meant To innovate Programming theory. It’s meant to Innovate programming practice." -- Samuel Tesla
7. "Why would you have a Language that is Not theoretically exciting? Because, it's very useful." -- Rob Pike paraphrased by Roger Peppe
8. Brought to you by... https://secure.flickr.com/photos/oreillyconf/4818477327/ Rob Pike Unix, Plan9, Google Ken Thompson Yeah, that Ken Thompson +
9. Quick stats: • Version 1 is now 43 43 days days old • Compiled language • Faster than Python • Garbage collection • Slower* than C *debatable • Production ready More details: • Officially announced Nov. 2009 • BSD license • Strong, static typing • Cross-platform
10. Execution time Where does Go fit in? Gets out of your way
11. Gets out of your way Execution time Python is really easy to read and write but execution time ins't always the best. Concurrency is available with tools like tornado but is not a “baked in” feature of the language. Python
12. Execution time As I see it, but I've never actually written any C code so, this placement is probably totally wrong. Python Gets out of your way
13. Execution time To me, Go is as clear and sensible as python but with performance characteristics closer to C. “C for the 21st century” - golang.org Python Gets out of your way
14. “Before Go, a developer had to choose between fast execution but slow and not efficient building (like C++), efficient compliation (but not so fast execution like .NET or Java), or ease of programming (but slower execution, like the dynamic languages): Go is an attempt to combine all three wishes: efficient and thus fast compilation, fast execution, ease of programming.” – Ivo Balbaert The Way to Go
15. Hello Go package main import ( “fmt” “math” ) func main() { fmt.Println(“Hello ひらが” ) fmt.Println(math.Pi) } Note the distinct lack of semi-colons
16. No headers package main import ( “fmt” “math” ) func main() { fmt.Println(“Hello ひらが” ) fmt.Println(math.Pi) } Each file is part of a package (namespace)
17. KISS package main import ( “fmt” “math” ) func main() { fmt.Println(“Hello ひらが” ) fmt.Println(math.Pi) } Pragmatism In action
18. Don't fight it package main import ( “fmt” “math” ) func main() { fmt.Println(“Hello ひらが” ) fmt.Println(math.Pi) } Must have main() function; Takes no arguments
19. Syntax package main import ( “fmt” “math” ) func main() { fmt.Println(“Hello ひらが” ) fmt.Println(math.Pi) } OOP syntax (Go isn't really OO though)
20. UTF-8 Everywhere package main import ( “fmt” “math” ) func main() { fmt.Println(“Hello ひらが” ) fmt.Println(math.Pi) } Unicode out of the box
21. So, what's the big deal then?
22. So, what's the big deal then? Concurrency Concurrency
23. Do not communicate by sharing memory; instead, share memory by Communicating. Communicating. --Effective Go
24. Goroutines and channels Goroutines are lightweight (around 4kb) functions running in the same address space. Not exactly the same as threads, coroutines or processes. func Announce(message string) { go func() { fmt.Println(message) }() } Conceptually similar to the & command in Unix to run a process in the background. Channels are how goroutines “talk” to each other, only one goroutine will ever have access to the data at any given time. c := make(chan int) go func() { list.Sort() c <- 1 }() doSomethingForAWhile() <-c In this example we make a channel of integers, call list.Sort() as a goroutine and when It's done, send the signal to c. We can call other functions while we wait for sort to finish. Once we get the signal, we can discard it.
25. Go makes multi-core / parallel / concurrent programming TRIVIAL TRIVIAL
26. Goal: Get to the web web as fast as you can
27. Goal: Get to the web web as fast as you can • Ruby has Sinatra
28. Goal: Get to the web web as fast as you can • Ruby has Sinatra • Python has web.py
29. Goal: Get to the web web as fast as you can • Ruby has Sinatra • Python has web.py • Go has web.go web.go
30. “web.go web.go is the simplest way to write web applications in the Go programming language. It's ideal for writing simple, performant backend web services. “ https://github.com/hoisie/web • Routing to url handlers based on regular expressions • Secure cookies • Support for fastcgi and scgi • Web applications are compiled to native code. This means very fast execution and page render speed • Efficiently serving static files
31. Conclusion Multiple cores? Parallelism? Compiling? Concurrency? Web apps? ARM? Databases? Networking? Systems???
32. Conclusion Multiple cores? Parallelism? Compiling? Concurrency? Web apps? ARM? Databases? Networking? Systems??? Stop worrying worrying. The gopher's got you covered.
33. Resources - Main site http://golang.org/ - In-browser, guided sandbox http://tour.golang.org - Step by step through samples http://golang.org/doc/codewalk/ - Community pakages http://godashboard.appspot.com/ - Books http://go-lang.cat-v.org/books Bindings for couch, mongo, riak, mysql, redis, even bitcoin.
34. Who is using Go? - Stathat -- http://blog.golang.org/2011/12/building-stathat-with-go.html - Google Thanksgiving doodle -- http://www.google.com/logos/2011/thanksgiving.html - Heroku - Cannonical - Atlassian - SmugMug Many others at http://go-lang.cat-v.org/
35. Image References • Gohper images from golang.org • http://cdn-ak.f.st-hatena.com/images/fotolife/d/debiandebian/20100410/20100410114455.png • http://www.unixica.com/images/thompson.jpeg • http://1.bp.blogspot.com/-ti6s2UsV8no/Tdn82ozbggI/AAAAAAAAABM/AS4-YcQWfgo/s1600/gopher.jpg%20border= • http://farm8.staticflickr.com/7209/6779040884_3f7bfeaf89_z.jpg • http://27.media.tumblr.com/tumblr_kt2ejqry4W1qz5wuco1_500.jpg Oh yeah. If you were curious:
36. Fonts from LOMT • League Gothic •Ostrich Sans • Junction
37. Presented to Presented to May 10, 2012 May 10, 2012 Slides available @ j.mp/go_satlug