The whole thing is kind of a mess.

implementations/oldlog/source/client/elm.json

@@ -0,0 +1,24 @@
+{
+    "type": "application",
+    "source-directories": [
+        "src"
+    ],
+    "elm-version": "0.19.1",
+    "dependencies": {
+        "direct": {
+            "elm/browser": "1.0.2",
+            "elm/core": "1.0.4",
+            "elm/html": "1.0.0",
+            "elm/url": "1.0.0"
+        },
+        "indirect": {
+            "elm/json": "1.1.3",
+            "elm/time": "1.0.0",
+            "elm/virtual-dom": "1.0.2"
+        }
+    },
+    "test-dependencies": {
+        "direct": {},
+        "indirect": {}
+    }
+}

implementations/oldlog/source/client/src/Main.elm

@@ -0,0 +1,116 @@
+module Main exposing (main)
+
+import Browser
+import Browser.Navigation as Nav
+import Html exposing (a, b, li, text, ul, Html)
+import Html.Attributes exposing (href)
+import Url
+import Url.Parser exposing (Parser, parse, string, s, (</>))
+
+-- MAIN
+main : Program () Model Msg
+main =
+  Browser.application
+    { init = init
+    , view = view
+    , update = update
+    , subscriptions = subscriptions
+    , onUrlChange = UrlChanged
+    , onUrlRequest = LinkClicked
+    }
+
+-- MODEL
+type alias Model =
+  { key : Nav.Key
+  , url : Url.Url
+  }
+
+
+init : () -> Url.Url -> Nav.Key -> ( Model, Cmd Msg )
+init _ url key =
+  -- ignore flags arg
+  ( Model key url, Cmd.none )
+
+-- UPDATE
+type Msg
+  = LinkClicked Browser.UrlRequest
+  | UrlChanged Url.Url
+
+
+update : Msg -> Model -> ( Model, Cmd Msg )
+update msg model =
+  case msg of
+    LinkClicked urlRequest ->
+      case urlRequest of
+        Browser.Internal url ->
+          -- Don't clutter browser history if the user clicks links to
+          -- the current URL.
+          if url == model.url then
+            ( model, Cmd.none )
+          else
+            ( model, Nav.pushUrl model.key (Url.toString url) )
+
+        Browser.External href ->
+          ( model, Nav.load href )
+
+    UrlChanged url ->
+      ( { model | url = url }
+      , Cmd.none
+      )
+
+-- SUBSCRIPTIONS
+
+subscriptions : Model -> Sub Msg
+subscriptions _ =
+  Sub.none
+
+-- VIEW
+
+view : Model -> Browser.Document Msg
+view model =
+  case parse docFunct model.url of
+    Nothing ->
+      viewGeneric (Url.toString model.url)
+    Just functor_name ->
+      viewFunctorDocs functor_name
+
+
+viewGeneric : String -> Browser.Document Msg
+viewGeneric current =
+  { title = "URL Interceptor: " ++ current
+  , body =
+      [ text "The current URL is: "
+      , b [] [ text current ]
+      , ul []
+          [ viewLink "Home" "/home"
+          , viewLink "Profile" "/profile"
+          , viewLink "Cent" "/reviews/the-century-of-the-self"
+          , viewLink "Pub" "/reviews/public-opinion"
+          , viewLink "cons" "/doc/functors/cons"
+          ]
+      ]
+  }
+
+
+viewFunctorDocs : String -> Browser.Document Msg
+viewFunctorDocs functor_name =
+  { title = "Reference: " ++ functor_name
+  , body =
+      [ text "Reference documentation for "
+      , b [] [ text functor_name ]
+      , ul []
+          [ viewLink "Home" "/home"
+          , viewLink "cons" "/doc/functors/cons"
+          ]
+      ]
+  }
+
+
+viewLink : String -> String -> Html msg
+viewLink link_text path =
+  li [] [ a [ href path ] [ text link_text ] ]
+
+
+docFunct : Parser (String -> a) a
+docFunct =
+  s "doc" </> s "functors" </> string