Move unescape map to Kernel for simplicity

lib/elixir/lib/kernel.ex

@@ -6188,16 +6188,25 @@ defmodule Kernel do
   defmacro sigil_r(term, modifiers)
 
   defmacro sigil_r({:<<>>, _meta, [string]}, options) when is_binary(string) do
-    binary = :elixir_interpolation.unescape_string(string, &Regex.unescape_map/1)
+    binary = :elixir_interpolation.unescape_string(string, &regex_unescape_map/1)
     regex = Regex.compile!(binary, :binary.list_to_bin(options))
     Macro.escape(regex)
   end
 
   defmacro sigil_r({:<<>>, meta, pieces}, options) do
-    binary = {:<<>>, meta, unescape_tokens(pieces, &Regex.unescape_map/1)}
+    binary = {:<<>>, meta, unescape_tokens(pieces, &regex_unescape_map/1)}
     quote(do: Regex.compile!(unquote(binary), unquote(:binary.list_to_bin(options))))
   end
 
+  defp regex_unescape_map(:newline), do: true
+  defp regex_unescape_map(?f), do: ?\f
+  defp regex_unescape_map(?n), do: ?\n
+  defp regex_unescape_map(?r), do: ?\r
+  defp regex_unescape_map(?t), do: ?\t
+  defp regex_unescape_map(?v), do: ?\v
+  defp regex_unescape_map(?a), do: ?\a
+  defp regex_unescape_map(_), do: false
+
   @doc ~S"""
   Handles the sigil `~R` for regular expressions.
 

lib/elixir/lib/regex.ex

@@ -852,19 +852,6 @@ defmodule Regex do
 
   # Helpers
 
-  @doc false
-  # Unescape map function used by Macro.unescape_string.
-  def unescape_map(:newline), do: true
-  def unescape_map(?f), do: ?\f
-  def unescape_map(?n), do: ?\n
-  def unescape_map(?r), do: ?\r
-  def unescape_map(?t), do: ?\t
-  def unescape_map(?v), do: ?\v
-  def unescape_map(?a), do: ?\a
-  def unescape_map(_), do: false
-
-  # Private Helpers
-
   defp translate_options(<<?u, t::binary>>, acc), do: translate_options(t, [:unicode, :ucp | acc])
   defp translate_options(<<?i, t::binary>>, acc), do: translate_options(t, [:caseless | acc])
   defp translate_options(<<?x, t::binary>>, acc), do: translate_options(t, [:extended | acc])