NYC CodeCamp 2011 Talk - Iron Languages, Dynamic Language on .NET

1. IRON Languages Jimmy Schementi jschementi@lab49.com jimmy.schementi.com Dynamic Languages for the .NET developer github.com/IronLanguages

2. JavaScript Tcl MATLAB Ruby Smalltalk

3. xkcd.com

4. Executes many common behaviors, at runtime, that other languages might perform during compilation, if at all.

5. Most are dynamically-typed, but not all. Dynamic Typing The majority of its type checking is performed at run-time as opposed to at compile-time.

6. why?

7. Simple enough for non-programmers, capable enough for programmers print File.read("foo.txt") name = "Jimmy" [1,2,3].each do |i| puts i end class Foo defmethod_missing(m) puts "called: #{m}" end end Foo.new.dfhajsdhfl "-" * 79 a.downcaserescue "No name"

8. Scripting Languages Dynamic Languages

9. “Python, like many good technologies, soon spreads virally throughout your development team and finds its way into all sorts of applications and tools…Python scripts are used in many areas of the game.” Mustafa Thamer Civilization IV development team

11. http://www.unreal.com/media/banners/kismet1.jpg

12. http://logo.twentygototen.org/

13. Interactive >>> 2 + 2 4

14. .NET?

15. Dynamic Languages on .NET Consumers

16. Keep it Simple Python Ruby def fact n return 1 if n == 0 n * fact(n-1) end puts fact 13 def fact(n): if n == 0: return 1 return n * fact(n-1) print fact(13) C# using System; public class MathClass { public static int Factorial(int n) { if (n == 0) return 1; return n * Factorial(n – 1); } public static void Main(string[] args) { Console.WriteLine(Factorial(13)); } }

17. Ecosystem exchange .NET gets Python and Ruby world, and Ruby/Python gets .NET world Ruby on Rails/Django/RSpec/etc on .NET Scripting the .NET framework Driving .NET code from scripts for testing, exploration, etc. DSL-like characteristics Hosting In-Application extensibility / customization Treating code as data (or configuration) Discussion on best practices

18. Scripting the .NET framework Driving .NET code from scripts Domain-specific languages Compiler Geek-Out High-level discussion on how compilers work and what the DLR does. Hosting In-Application extensibility / customization Treating code as data (or configuration) Discussion on best practices

19. Demo Scripting .NET

20. rb> puts 2 + 2 4 # => nil

21. traditional compiler front-end Scan Token stream def add(): return 2 + a return 2 + a Parse Syntax Tree return add Named(a) Const(2)

22. IronPython: Hand-written LL(1) parser IronRuby: Gardens Point Parser Generator LALR(1)

23. compiler back-end on CLR Generate IL Syntax Tree ldc.i4.2 // load 2 box [mscorlib]System.Int32 ldarg.0 // load “a” call object LangHelpers::Add(object, object) ret IL return add public static object Add (object x, object y) { ... } Const(2) Runtime Library Named(a)

24. compiler back-end on DLR Linq Expression Tree ToExpression Tree Return Syntax Tree return MethodCall LangHelpers.Add add ConvertTo Object BoundExpression Const(2) Named(a) Variable a: Object ConstantExpression 2

25. puts 2 + 2 -> Expression tree .Dynamic puts(.S,1) @1( $#scope, $#self, .Call IronRuby.Runtime.RubyOps.CreateMutableStringL( "hi", .Constant<IronRuby.Builtins.RubyEncoding>(US-ASCII)))

26. IronRuby.Runtime.RubyScriptCode internalstaticDelegate/*!*/CompileLambda( LambdaExpression/*!*/ lambda, booldebugMode, boolnoAdaptiveCompilation, intcompilationThreshold) { if (debugMode) { returnCompileDebug(lambda); } elseif (noAdaptiveCompilation) { returnlambda.Compile(); } else { returnlambda.LightCompile(compilationThreshold); } }

27. static vs. dynamic dispatch MethodCallExpression Method : {RuntimeMethodInfo {Name: "Print"}} Arguments : [0] ActionExpression def yo (name): "hello " + name print yo("jimmy") ActionExpression yo("jimmy") Action : CallAction Arguments : [0] {BoundExpression {Variable: Local{yo}}} [1] {ConstantExpression {"jimmy"}}

28. public static object Handle ( object[] args, DynamicSite<object, object, object> site1, object obj1, object obj2) { if (obj1 != null && obj1.GetType() == typeof(string) && obj2 != null && obj2.GetType() == typeof(string)) { return StringOps.Add(Converter.ConvertToString(obj1), Converter.ConvertToString(obj2)); } return site1.UpdateBindingAndInvoke(obj1, obj2); }

29. print yo(1)

30. public static object Handle ( object[] args, DynamicSite<object, object, object> site1, object obj1, object obj2) { if (obj1 != null && obj1.GetType() == typeof(int) && obj2 != null && obj2.GetType() == typeof(int)) { return Int32Ops.Add(Converter.ConvertToInt(obj1), Converter.ConvertToInt(obj2)); } if (obj1 != null && obj1.GetType() == typeof(string) && obj2 != null && obj2.GetType() == typeof(string)) { return StringOps.Add(Converter.ConvertToString(obj1), Converter.ConvertToString(obj2)); } return site1.UpdateBindingAndInvoke(obj1, obj2); }

31. System.Dynamic.DynamicObject

32. Dynamic Language Runtime Infrastructure for creating languages Focus on dynamic compiler back-end. Dynamic-lookup protocol DynamicObject: shared protocol between languages Lightweight hosting API One API for all DLR languages

33. Hosting Hosting ScriptRuntime ScriptScope ScriptEngine ScriptSource

34. var engine = Ruby.CreateEngine(); engine.Execute("puts 2 + 2");

35. var engine = Python.CreateEngine(); dynamicscope = engine.CreateScope(); scope.page= this; engine.Execute("page.Message.Text = 'Hello from Python!'", scope);

36. var runtime = ScriptRuntime.CreateFromConfiguration(); var engine = ScriptEngine.CreateEngine("IronRuby"); dynamic scope = engine.CreateScope(); scope.page = this;engine.Execute("page.Message.Text = 'Hello from IronRuby!'", scope);

37. require 'IronPython'require 'Microsoft.Scripting'include Microsoft::Scripting::Hostinginclude IronPython::Hostingpython = Python.create_enginescope = python.create_scopepython.execute "class Foo(object): def bar(self): print 'Look ma, white-space-sensitivity!'", scopepython.execute "Foo().bar()", scope

38. # foo.py:class Foo(object): def bar(self): print 'Look ma, white-space-sensitivity!' # bar.rb:foo_module = IronRuby.require 'foo' foo_module.foo.bar

39. Demo Hosting

40. Hosting best-practices Store scripts where you want with PlatformAdaptationLayer Makes script file-system operations use database, source-control, whatever … Pick isolation level for scripts In-App-Domain: you totally control Out-App-Domain: limit permission level Out of process: total isolation

41. Project Status IronRubyis working towards 1.9 compat – Rails 3, FFI, static type system integration IronPythonworking towards 2.7/3.0 compat – Django, IronClad, and other libraries. Tooling IronRuby Gems/Rake support Debugging w/REPL Fully open source Contributions welcome!

42. How you can participate Use it at your company, and tell us about it! Ask the mailing lists and stackoverflow for help Log any bugs you find Contributing to the project Even if you’re not a compiler hacker … but hackers welcome! samples, documentation, blogs, and talks are all welcome also

43. ironruby.netIronRuby website & download ironpython.netIronPython website & downloaddlr.codeplex.comDLR documentation for hosters and language developersjimmy.schementi.comme

44. ?

45. IRON Languages Jimmy Schementi jschementi@lab49.com jimmy.schementi.com Dynamic Languages for the .NET developer github.com/IronLanguages