Introduce phantom file

src/Internal/Config/Phantom.elm

@@ -0,0 +1,51 @@
+module Internal.Config.Phantom exposing (PString(..), PInt(..), PBool(..), PList(..))
+
+{-|
+
+
+# Phantom types
+
+This module contains a lot of phantom types that do not necessarily do anything,
+but they force the compiler to create an error whenever something illegal is
+done.
+
+Compiler errors may seem annoying, they can help you write good code. In a
+functional programming language like Elm, the trick is to design your code in
+such a way that if it compiles, it works. Phantom types can help you do so.
+
+The phantom types in this module help you in the following way:
+
+1.  They can help force an compile to fault when you forget to run a function.
+
+2.  They can help track values for security.
+
+
+## Standard data types
+
+@docs PString, PInt, PBool, PList
+
+-}
+
+
+{-| Opaque type that encapsulates a bool.
+-}
+type PBool a
+    = PBool Bool
+
+
+{-| Opaque type that encapsulates an int.
+-}
+type PInt ph
+    = PInt Int
+
+
+{-| Opaque type that encapsulates a list.
+-}
+type PList ph a
+    = PList (List a)
+
+
+{-| Opaque type that encapsulates a string.
+-}
+type PString ph
+    = PString String