2 files changed, 48 insertions(+), 14 deletions(-)

M lib/lixp.ex
M lib/lixp/parser.ex

@@ 1,30 1,64 @@
 defmodule Lixp do
   def eval(str) do
-    {:ok, [res], _, _, _, _} = Lixp.Parser.program(str)
-    eval(res, %{})
+    {:ok, prog, _, _, _, _} = Lixp.Parser.program(str)
+  
+    {val, _} =
+      Enum.reduce(prog, {nil, %{}}, fn p, {_, e} ->
+        eval(p, e)
+      end)
+  
+    val
   end
-  defp eval(num, _env) when is_number(num) do
-    num
+  defp eval(num, env) when is_number(num) do
+    {num, env}
   end
-  defp eval(atom, _env) when is_atom(atom) do
-    atom
+  defp eval(atom, env) when is_atom(atom) do
+    {atom, env}
   end
   defp eval({:symbol, sym}, env) do
-    env[sym]
+    {env[sym], env}
+  end
+  defp eval([{:symbol, "quote"} | [rest]], env) do
+    rest = Enum.map(rest, fn
+      [{:symbol, "unquote"} | [body]] ->
+        {val, _} = eval(body, env)
+        val
+      x -> x
+    end)
+  
+    {rest, env}
+  end
+  defp eval([{:symbol, "ffi"} | rest], env) do
+    [m, f, a] = rest
+    {m, env} = eval(m, env)
+    {f, env} = eval(f, env)
+    {a, env} = eval(a, env)
+    {apply(m, f, a), env}
+  end
+  defp eval([{:symbol, "define"} | rest], env) do
+    [{:symbol, name}, body] = rest
+    {val, env} = eval(body, env)
+    env = Map.put(env, name, val)
+  
+    {val, env}
   end
   defp eval([{:symbol, "lambda"} | rest ], env) do
     [ arg_names | [body] ] = rest
-    fn args ->
+    {fn args ->
       arg_names = Enum.map(arg_names, fn {:symbol, name} -> name end)
       combination = Enum.zip(arg_names, args)
-      eval(body, extend(combination, env))
-    end
+      {val, _} = eval(body, extend(combination, env))
+      val
+    end, env}
   end
   defp eval([h | t], env) do
-    f = eval(h, env)
-    args = Enum.map(t, &eval(&1, env))
+    {f, env} = eval(h, env)
+    args = Enum.map(t, fn x ->
+      {val, _} = eval(x, env)
+      val
+    end)
   
-    f.(args)
+    {f.(args), env}
   end
   defp extend([{name, val} | rest], env) do
     extend(rest, Map.put(env, name, val))

@@ 64,7 64,7 @@ defmodule Lixp.Parser do
     )
   defparsec(
     :term,
-    choice([list, number(), atom, symbol, ignore(string(" "))])
+    choice([list, number(), atom, symbol, ignore(string(" ")), ignore(string("\n"))])
   )
   
   defparsec(