lecture 05

lectures/05/lec5a.ex

@@ -0,0 +1,32 @@
+defmodule M do
+	def if_fun(predicate, do: do_block, else: else_block) do
+		cond do
+			predicate -> do_block
+			true -> else_block
+		end
+	end
+
+	defmacro inspect(x) do
+		IO.inspect(x)
+	end
+
+	defmacro if_macro(predicate, do: do_block, else: else_block) do
+		quote do
+			cond do
+				unquote(predicate) -> unquote(do_block)
+				true -> unquote(else_block)
+			end
+		end
+	end
+
+	defmacro while(condition, do: do_block) do
+		quote do
+			try do
+				for _ <- Stream.cycle [:ok] do
+					if unquote(condition), do: unquote(do_block),
+					else: throw :break
+				end
+			catch :throw, :break -> :ok end
+		end
+	end
+end