namespace attributes

import Boo.Lang.Compiler
import Boo.Lang.Compiler.Ast
import Boo.Lang.Compiler.MetaProgramming

class NotNullAttribute(AbstractAstAttribute):
	override def Apply(node as Node):
		p as ParameterDeclaration = node
		
		method as Method = p.ParentNode
		method.Body = [|
			if $p is null: raise System.ArgumentNullException($(p.Name))
			$(method.Body)
		|]

code = [|
	import attributes

	class Lumberjack:
		def sing([NotNull] song):
			print song
|]
type = compile(code).GetType("Lumberjack")

lumberjack as duck = type()
lumberjack.sing(null)

#print code.ToCodeString()