WIP

lib/lytlang.ex

@@ -1,23 +1,28 @@
 defmodule Lytlang do
+  @root_module :Lytlang
+
   def eval(string) do
     {value, _} =
       string
       |> from_lytlang()
-      |> IO.inspect()
       |> Code.eval_quoted()
-      |> IO.inspect()
 
     value
   end
 
   def from_lytlang(string, binding \\ [], opts \\ []) do
-    string |> String.to_charlist() |> tokenize() |> parse() |> transform(binding, opts)
+    string
+    |> String.to_charlist()
+    |> tokenize()
+    |> parse()
+    |> to_ast_node(binding, opts)
+    |> to_elixir_ast(opts)
   end
 
   def tokenize(string) do
     {:ok, tokens, _} =
       :lytlang_lexer.string(string)
-      |> IO.inspect()
+      |> IO.inspect(label: "Tokens")
 
     tokens
   end
@@ -25,28 +30,77 @@ defmodule Lytlang do
   def parse(tokens) do
     {:ok, tree} =
       :lytlang_parser.parse(tokens)
-      |> IO.inspect()
+      |> IO.inspect(label: "Parsed")
 
     tree
   end
 
-  def transform(ast, binding \\ [], opts \\ [])
+  @type astnode :: {any, {keyword, keyword, keyword}, list}
+  @type ex_astnode :: {any, keyword, any}
 
-  def transform([] = _expr_list, _binding, _opts), do: []
+  # @spec to_elixir_ast(astnode, keyword) :: ex_astnode
+  def to_elixir_ast(astnode, opts \\ [])
 
-  def transform([expr | rest] = _expr_list, binding, opts) do
+  def to_elixir_ast(s, opts) when is_list(s) do
-    [transform(expr, binding, opts) | transform(rest, binding, opts)]
+    Enum.map(s, fn node ->
+      to_elixir_ast(node, opts)
+    end)
   end
 
-  def transform({:binary_op, _line, op, left, right}, binding, _) do
+  def to_elixir_ast({{:literal, expr}, {_meta, _binding, _ast_opts}, _leaves}, _opts) do
-    {op, binding, [transform(left), transform(right)]}
+    expr
+    |> IO.inspect(label: "EX AST")
   end
 
-  def transform({:unary_op, line, op, left}, _, _) do
+  def to_elixir_ast({s, {_meta, binding, _ast_opts}, leaves}, _opts) do
-    {:op, line, op, transform(left)}
+    {s, binding, to_elixir_ast(leaves)}
+    |> IO.inspect(label: "EX AST")
   end
 
-  def transform({:integer, _, n} = _expr, _, _), do: n
+  @spec to_ast_node(any, keyword, keyword) :: astnode
+  def to_ast_node(ast, binding \\ [], opts \\ [])
+
+  def to_ast_node([], binding, opts), do: {[], {binding, opts}}
+
+  def to_ast_node(expr_list, binding, opts) when is_list(expr_list) do
+    Enum.reduce(expr_list, {nil, {[], binding, opts}, []}, fn expr,
+                                                              {_s, {_meta, binding, opts},
+                                                               _operands} ->
+      {s, {nmeta, nbinding, nopts}, operands} = to_ast_node(expr, binding, opts)
+
+      {s, {nmeta, Keyword.merge(binding, nbinding), Keyword.merge(opts, nopts)}, operands}
+    end)
+  end
+
+  def to_ast_node({:list_op, line, op, operands}, binding, opts) when is_list(operands) do
+    {op, {[line: line], binding, opts},
+     [Enum.map(operands, fn o -> to_ast_node(o, binding, opts) end)]}
+  end
+
+  def to_ast_node({:binary_op, line, op, left, right}, binding, opts) do
+    {op, {[line: line], binding, opts}, [to_ast_node(left), to_ast_node(right)]}
+  end
+
+  def to_ast_node({:unary_op, line, op, left}, binding, opts) do
+    {op, {[line: line], binding, opts}, [to_ast_node(left)]}
+  end
+
+  def to_ast_node({:var, line, left} = _expr, binding, opts) do
+    # TODO: probably need to look in bindings? or shadowing so maybe not?
+    to_ast_node({:unary_op, line, left, {:literal, line, @root_module}}, binding, opts)
+  end
+
+  def to_ast_node({:match, line, left, right} = _expr, binding, opts) do
+    to_ast_node({:binary_op, line, :=, left, right}, binding, opts)
+  end
+
+  def to_ast_node({:integer, line, val} = _expr, binding, opts) do
+    to_ast_node({:literal, line, val}, binding, opts)
+  end
+
+  def to_ast_node({:literal, line, val} = _expr, binding, opts) do
+    {{:literal, val}, {[line: line], binding, opts}, []}
+  end
 end
 
 """

src/lytlang_lexer.xrl

@@ -7,6 +7,7 @@ D = [0-9]
 U = [A-Z]
 L = [a-z]
 WS = [\s]
+LF = \n
 
 Rules.
 
@@ -22,10 +23,13 @@ Rules.
 \)    : { token, { ')', TokenLine } }.
 =     : { token, { '=', TokenLine } }.
 ->    : { token, { '->', TokenLine } }.
-;     : { token, { ';', TokenLine } }.
+;     : { token, { eol, TokenLine } }.
+{LF}  : { token, { eol, TokenLine } }.
 
 {Comment} : skip_token.
 {WS}+ : skip_token.
+% {LF}+ : skip_token.
+% {CRLF}+ : skip_token.
 % ({Comment}|{Whitespace})*(\n({Comment}|{Whitespace})*)+ : { token, { eol, TokenLine } }.
 
 Erlang code.

src/lytlang_parser.yrl

@@ -63,6 +63,7 @@ fun_expr -> stabber eol body :
 fun_expr -> max_expr : '$1'.
 
 %% Minimum expressions
+max_expr -> var : '$1'.
 max_expr -> number : '$1'.
 max_expr -> '(' expr ')' : '$2'.
 

test/lytlang_test.exs

@@ -12,6 +12,7 @@ defmodule LytlangTest do
       {"2 + (3 * 8)", 26},
       {"8 - 3", 5},
       {"8 / 4", 2.0},
+      {"a = 8\na + 9", 17},
       {"2 + 3", 5}
     ]
     |> Enum.map(fn {string, val} ->