WIP: implement the DOM

content/navigation.nix

@@ -6,7 +6,6 @@ in
   menus.main = {
     label = "Main";
     items = [
-      { page = pages.index // { title = "Start"; }; }
       {
         menu.label = "For you";
         menu.items = map (page: { inherit page; })

lib.nix

@@ -1,19 +1,5 @@
 { lib }:
 rec {
-  /**
-    Recursively replace occurrences of `from` with `to` within `string`
-
-    Example:
-
-        replaceStringRec "--" "-" "hello-----world"
-        => "hello-world"
-  */
-  replaceStringsRec = from: to: string:
-    let
-      replaced = lib.replaceStrings [ from ] [ to ] string;
-    in
-    if replaced == string then string else replaceStringsRec from to replaced;
-
   /**
     Create a URL-safe slug from any string
   */
@@ -36,30 +22,14 @@ rec {
           matched = builtins.match "(-*)([^-].*[^-]|[^-])(-*)" s;
         in
         with lib; optionalString (!isNull matched) (builtins.elemAt matched 1);
-    in
-    trimHyphens (replaceStringsRec "--" "-" replaced);
 
-  squash = replaceStringsRec "\n\n" "\n";
-
-  /**
-    Trim trailing spaces and squash non-leading spaces
-  */
-  trim = string:
-    let
-      trimLine = line:
-        with lib;
+      collapseHyphens = s:
         let
-          # separate leading spaces from the rest
-          parts = split "(^ *)" line;
-          spaces = head (elemAt parts 1);
-          rest = elemAt parts 2;
-          # drop trailing spaces
-          body = head (split " *$" rest);
+          result = builtins.replaceStrings [ "--" ] [ "-" ] s;
         in
-        if body == "" then "" else
-        spaces + replaceStringsRec "  " " " body;
+        if result == s then s else collapseHyphens result;
     in
-    join "\n" (map trimLine (splitLines string));
+    trimHyphens (collapseHyphens replaced);
 
   join = lib.concatStringsSep;
 

presentation/default.nix

@@ -5,14 +5,6 @@ let
     types
     ;
   templates = import ./templates.nix { inherit lib; };
-  render-html = document:
-    let
-      eval = lib.evalModules {
-        class = "DOM";
-        modules = [ document (import ./dom.nix { inherit lib; }).document ];
-      };
-    in
-    toString eval.config;
 in
 {
   options.templates =
@@ -46,38 +38,30 @@ in
     in
     {
       nav = lib.mkDefault templates.nav;
-      page = lib.mkDefault (config: page: render-html {
-        html = {
-          head = {
-            title.text = page.title;
-            meta.description = page.description;
-            link.canonical = lib.head page.locations;
-          };
-          body.content = ''
-            ${config.menus.main.outputs.html page}
-
-            <h1>${page.title}</h1>
-
-            ${builtins.readFile (commonmark page.name page.body)}
-          '';
-        };
+      page = lib.mkDefault (config: page: templates.html {
+        head = ''
+          <title>${page.title}</title>
+          <meta name="description" content="${page.description}" />
+          <link rel="canonical" href="${lib.head page.locations}" />
+        '';
+        body = ''
+          ${config.menus.main.outputs.html page}
+          ${builtins.readFile (commonmark page.name page.body)}
+        '';
       });
-      article = lib.mkDefault (config: page: render-html {
-        html = {
-          head = {
-            title.text = page.title;
-            meta.description = page.description;
-            meta.authors = if lib.isList page.author then page.author else [ page.author ];
-            link.canonical = lib.head page.locations;
-          };
-          body.content = ''
-            ${config.menus.main.outputs.html page}
-
-            <h1>${page.title}</h1>
-
-            ${builtins.readFile (commonmark page.name page.body)}
-          '';
-        };
+      article = lib.mkDefault (config: page: templates.html {
+        head = ''
+          <title>${page.title}</title>
+          <meta name="description" content="${page.description}" />
+          ${with lib; join "\n" (map
+          (author: ''<meta name="author" content="${author}" />'')
+          (if isList page.author then page.author else [page.author]))
+          }
+        '';
+        body = ''
+          ${config.menus.main.outputs.html page}
+          ${builtins.readFile (commonmark page.name page.body)}
+        '';
       });
     };
 

presentation/dom.nix

@@ -7,8 +7,6 @@
 */
 { lib, ... }:
 let
-  inherit (lib) mkOption types;
-
   # https://html.spec.whatwg.org/multipage/dom.html#content-models
   # https://html.spec.whatwg.org/multipage/dom.html#kinds-of-content
   content-categories = [
@@ -27,8 +25,6 @@ let
 
   # base type for all DOM elements
   element = { name, config, ... }: {
-    # TODO: add fields for upstream documentation references
-    # TODO: programmatically generate documentation
     options = with lib; {
       attrs = mkAttrs { };
       categories = mkOption {
@@ -43,7 +39,7 @@ let
 
   # options with types for all the defined DOM elements
   element-types = lib.mapAttrs
-    (name: value: mkOption { type = types.submodule value; })
+    (name: value: mkOption { type = types.submodule e; })
     elements;
 
   # attrset of categories, where values are module options with the type of the
@@ -57,98 +53,57 @@ let
           (filterAttrs (_: e: elem category (e { name = "dummy"; }).config.categories) elements))
       );
 
-  global-attrs = lib.mapAttrs (name: value: mkOption value) {
-    class = {
-      type = with types; listOf nonEmptyStr;
-      default = [ ];
-    };
-    hidden = {
-      type = types.bool;
-      default = false;
-    };
-    id = {
-      type = with types; nullOr nonEmptyStr;
-      default = null;
-    };
-    lang = {
-      # TODO: https://www.rfc-editor.org/rfc/rfc5646.html
-      type = with types; nullOr str;
-      default = null;
-    };
-    style = {
-      # TODO: CSS type ;..)
-      type = with types; nullOr str;
-      default = null;
-    };
-    title = {
-      type = with types; nullOr lines;
-      default = null;
-    };
-    # TODO: more global attributes
-    # https://html.spec.whatwg.org/#global-attributes
-    # https://html.spec.whatwg.org/#attr-aria-*
-    # https://html.spec.whatwg.org/multipage/microdata.html#encoding-microdata
-  };
-
-  attrs = lib.mapAttrs (name: value: mkOption value) {
-    href = {
-      # TODO: https://url.spec.whatwg.org/#valid-url-string
-      # ;..O
-      type = types.str;
-    };
-    target = {
-      # https://html.spec.whatwg.org/multipage/document-sequences.html#valid-navigable-target-name-or-keyword
-      type =
-        let
-          is-valid-target = s:
-            let
-              inherit (lib) match;
-              has-lt = s: match ".*<.*" s != null;
-              has-tab-or-newline = s: match ".*[\t\n].*" s != null;
-              has-valid-start = s: match "^[^_].*$" s != null;
-            in
-            has-valid-start s && !(has-lt s && has-tab-or-newline s);
-        in
-        with types; either
-          (enum [ "_blank" "_self" "_parent" "_top" ])
-          (types.addCheck str is-valid-target)
-      ;
-    };
-  };
-
-  mkAttrs = attrs: with lib;
-    mkOption {
-      type = types.submodule {
-        options = global-attrs // attrs;
-      };
-      default = { };
-    };
-
-  print-attrs = with lib; attrs:
-    # TODO: figure out how let attributes know how to print themselves without polluting the interface
+  global-attrs =
     let
-      result = trim (join " "
-        (mapAttrsToList
-          # TODO: this needs to be smarter for boolean attributes
-          #       where the value must be written out explicitly.
-          #       probably the attribute itself should have its own `__toString`.
-          (name: value:
-            if isBool value then
-              if value then name else ""
-            # TODO: some attributes must be explicitly empty
-            else optionalString (toString value != "") ''${name}=${value}''
-          )
-          attrs)
-      );
+      inherit (lib) mkOption types;
     in
-    optionalString (stringLength result > 0) " " + result
-  ;
+    {
+      class = mkOption {
+        type = with types; listOf nonEmptyStr;
+      };
+      hidden = mkOption {
+        type = types.bool;
+      };
+      id = mkOption {
+        type = types.nonEmptyStr;
+      };
+      lang = mkOption {
+        # TODO: https://www.rfc-editor.org/rfc/rfc5646.html
+        type = types.str;
+      };
+      style = mkOption {
+        # TODO: CSS type ;..)
+        type = types.str;
+      };
+      title = mkOption {
+        type = types.lines;
+      };
+      # TODO: more global attributes
+      # https://html.spec.whatwg.org/#global-attributes
+      # https://html.spec.whatwg.org/#attr-aria-*
+      # https://html.spec.whatwg.org/multipage/microdata.html#encoding-microdata
+    };
+
+  mkAttrs = attrs: with lib; mkOption {
+    type = types.submodule {
+      options = global-attrs // attrs;
+    };
+    default = { };
+  };
 
   print-element = name: attrs: content:
     with lib;
+    let
+      attributes = join " " (mapAttrsToList
+        # TODO: this needs to be smarter for boolean attributes
+        #       where the value must be written out explicitly.
+        #       probably the attribute itself should have its own `__toString`.
+        (name: value: if isBool value then name else "${name}=${value}")
+        attrs);
+    in
     lib.squash ''
-      <${name}${print-attrs attrs}>
-        ${lib.indent "  " content}
+      <${name}${optionalString (stringLength attributes > 0) " ${attributes}"}>
+         ${lib.indent "  " content}
       </${name}>
     '';
 
@@ -161,7 +116,7 @@ let
 
       config.categories = [ ];
       config.__toString = self: ''
-        <!DOCTYPE HTML >
+        <!DOCTYPE HTML>
         ${self.html}
       '';
     };
@@ -191,175 +146,32 @@ let
           type = with types; nullOr (submodule base);
           default = null;
         };
-        # https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-charset
-        meta.charset = mkOption {
-          # TODO: create programmatically from https://encoding.spec.whatwg.org/encodings.json
-          type = types.enum [
-            "utf-8"
-          ];
-          default = "utf-8";
-        };
-        # https://developer.mozilla.org/en-US/docs/Web/HTML/Viewport_meta_tag#viewport_width_and_screen_width
-        # this should not exist and no one should ever have to think about it
-        meta.viewport = mkOption {
-          type = types.submodule ({ ... }: {
-            # TODO: figure out how to render only non-default values
-            options = {
-              width = mkOption {
-                type = with types; either
-                  (ints.between 1 10000)
-                  (enum [ "device-width" ]);
-                default = "device-width"; # not default by standard
-              };
-              height = mkOption {
-                type = with types; either
-                  (ints.between 1 10000)
-                  (enum [ "device-height" ]);
-                default = "device-height"; # not default by standard (but seems to work if you don't set it)
-              };
-              initial-scale = mkOption {
-                type = types.numbers.between 0.1 10;
-                default = 1;
-              };
-              minimum-scale = mkOption {
-                type = types.numbers.between 0.1 10;
-                # TODO: render only as many digits as needed
-                default = 0.1;
-              };
-              maximum-scale = mkOption {
-                type = types.numbers.between 0.1 10;
-                default = 10;
-              };
-              user-scalable = mkOption {
-                type = types.bool;
-                default = true;
-              };
-              interactive-widget = mkOption {
-                type = types.enum [
-                  "resizes-visual"
-                  "resizes-content"
-                  "overlays-content"
-                ];
-                default = "resizes-visual";
-              };
-            };
-          });
-          default = { };
-        };
-
-        meta.authors = mkOption {
-          type = with types; listOf str;
-          default = [ ];
-        };
-        meta.description = mkOption {
-          type = with types; nullOr str;
-          default = null;
-        };
-        link.canonical = mkOption {
-          type = with types; nullOr str;
-          default = null;
-        };
-
-        # TODO: figure out `meta` elements
-        # https://html.spec.whatwg.org/multipage/semantics.html#the-meta-element:concept-element-attributes
-        # https://html.spec.whatwg.org/multipage/semantics.html#other-metadata-names
+        content = with types;
+          listOf (attrTag (
+            removeAttrs categories.metadata [ "title" "base" ]
+          ));
       };
 
       config.categories = [ ];
-      config.__toString = self:
-        with lib;
-        print-element name self.attrs ''
-          ${self.title}
-          ${with lib; optionalString (!isNull self.base) self.base}
-          <meta charset="${self.meta.charset}" />
-
-          ${/* https://html.spec.whatwg.org/multipage/semantics.html#attr-meta-http-equiv-x-ua-compatible */
-          ""}<meta http-equiv="X-UA-Compatible" content="IE=edge" />
-
-          <meta name="viewport" content="${join ", " (mapAttrsToList
-            (name: value: "${name}=${toString value}") self.meta.viewport)
-          }" />
-
-          ${join "\n" (map
-              (author: ''<meta name="author" content="${author}" />'')
-            self.meta.authors)
-          }
-        '';
+      config.__toString = self: print-element name self.attrs ''
+        ${self.title}
+        ${with lib; optionalString (!isNull self.base) self.base}
+        ${join "\n" (map (s: "${s}") self.content)}
+      '';
     };
 
     title = { name, ... }: {
-      imports = [ element ];
-      options.text = mkOption {
-        type = types.str;
-      };
+      # TODO
       config.categories = [ "metadata" ];
-      config.__toString = self: "<${name}${print-attrs self.attrs}>${self.text}</${name}>";
 
     };
-
     base = { name, ... }: {
-      imports = [ element ];
-      # TODO: "A base element must have either an href attribute, a target attribute, or both."
-      attrs = mkAttrs { inherit (attrs) href target; };
+      # TODO
       config.categories = [ "metadata" ];
     };
 
-    link = { name, ... }: {
-      imports = [ element ];
-      options = mkAttrs
-        {
-          # TODO: more attributes
-          # https://html.spec.whatwg.org/multipage/semantics.html#the-link-element:concept-element-attributes
-          inherit (attrs) href;
-        } // {
-        # XXX: there are variants of `rel` for `link`, `a`/`area`, and `form`
-        rel = mkOption {
-          # https://html.spec.whatwg.org/multipage/semantics.html#attr-link-rel
-          type = with types; listOfUnique str (enum
-            # TODO: work out link types in detail, there are lots of additional constraints
-            # https://html.spec.whatwg.org/multipage/links.html#linkTypes
-            [
-              "alternate"
-              "dns-prefetch"
-              "expect"
-              "help"
-              "icon"
-              "license"
-              "manifest"
-              "modulepreload"
-              "next"
-              "pingback"
-              "preconnect"
-              "prefetch"
-              "preload"
-              "prev"
-              "privacy-policy"
-              "search"
-              "stylesheet"
-              "terms-of-service"
-            ]
-          );
-        };
-      };
-      # TODO: figure out how to make body-ok `link` elements
-      # https://html.spec.whatwg.org/multipage/semantics.html#allowed-in-the-body
-      config.categories = [ "metadata" ];
-      config.__toString = self: "<name${print-attrs self.attrs} />";
-    };
-
     body = { name, ... }: {
-      imports = [ element ];
-      options = {
-        content = mkOption {
-          type = with types;
-            # HACK: bail out for now
-            # TODO: find a reasonable cut-off for where to place raw content
-            either str (listOf (attrTag categories.flow));
-        };
-      };
-      config.categories = [ ];
-      config.__toString = self: with lib;
-        if isList self.content then join "\n" (toString self.content) else self.content;
+      # TODO
     };
   };
 in

presentation/templates.nix

@@ -1,5 +1,19 @@
 { lib }:
 rec {
+  html = { head, body }: ''
+    <!DOCTYPE html>
+    <html>
+      <head>
+        <meta charset="utf-8" />
+        <meta http-equiv="X-UA-Compatible" content="IE=edge" />
+        <meta name="viewport" content="width=device-width, initial-scale=1" />
+        ${lib.indent "    " head}
+      </head>
+      <body>
+        ${lib.indent "    " body}
+      <body>
+    </html>
+  '';
   nav = menu: page:
     let
       render-item = item:

structure/default.nix

@@ -22,60 +22,62 @@ in
     type = with types; attrsOf (submodule config.content-types.page);
   };
 
-  options.collections = mkOption {
-    description = ''
-      Named collections of unnamed pages
+  options.collections = mkOption
+    {
+      description = ''
+        Named collections of unnamed pages
 
-      Define the content type of a new collection `example` to be `article`:
+        Define the content type of a new collection `example` to be `article`:
 
-      ```nix
-      config.collections.example.type = config.types.article;
-      ```
+        ```nix
+        config.collections.example.type = config.types.article;
+        ```
 
-      Add a new entry to the `example` collection:
+        Add a new entry to the `example` collection:
 
-      ```nix
-      config.collections.example.entry = {
-        # contents here
-      }
-      ```
-    '';
-    type = with types; attrsOf (submodule ({ name, config, ... }: {
-      options = {
-        type = mkOption {
-          description = "Type of entries in the collection";
-          type = types.deferredModule;
+        ```nix
+        config.collections.example.entry = {
+          # contents here
+        }
+        ```
+      '';
+      type = with types; attrsOf (submodule ({ name, config, ... }: {
+        options = {
+          type = mkOption {
+            description = "Type of entries in the collection";
+            type = types.deferredModule;
+          };
+          name = mkOption {
+            description = "Symbolic name, used as a human-readable identifier";
+            type = types.str;
+            default = name;
+          };
+          prefixes = mkOption {
+            description = ''
+              List of historic output locations for files in the collection
+
+              The first element is the canonical location.
+              All other elements are used to create redirects to the canonical location.
+
+              The default entry is the symbolic name of the collection.
+              When changing the symbolic name, append the old one to your custom list and use `lib.mkForce` to make sure the default element will be overridden.
+            '';
+            type = with types; nonEmptyListOf str;
+            example = [ "." ];
+            default = [ config.name ];
+          };
+          entry = mkOption
+            {
+              description = "An entry in the collection";
+              type = types.collection (types.submodule ({
+                imports = [ config.type ];
+                _module.args.collection = config;
+                process-locations = ls: with lib; concatMap (l: map (p: "${p}/${l}") config.prefixes) ls;
+              }));
+            };
         };
-        name = mkOption {
-          description = "Symbolic name, used as a human-readable identifier";
-          type = types.str;
-          default = name;
-        };
-        prefixes = mkOption {
-          description = ''
-            List of historic output locations for files in the collection
-
-            The first element is the canonical location.
-            All other elements are used to create redirects to the canonical location.
-
-            The default entry is the symbolic name of the collection.
-            When changing the symbolic name, append the old one to your custom list and use `lib.mkForce` to make sure the default element will be overridden.
-          '';
-          type = with types; nonEmptyListOf str;
-          example = [ "." ];
-          default = [ config.name ];
-        };
-        entry = mkOption {
-          description = "An entry in the collection";
-          type = types.collection (types.submodule ({
-            imports = [ config.type ];
-            _module.args.collection = config;
-            process-locations = ls: with lib; concatMap (l: map (p: "${p}/${l}") config.prefixes) ls;
-          }));
-        };
-      };
-    }));
-  };
+      }));
+    };
 
   options.menus = mkOption {
     description = ''

structure/document.nix

@@ -46,8 +46,6 @@ in
         default = target: with lib; "${relativePath (head config.locations) (head target.locations)}.html";
       };
       outputs = mkOption {
-        # TODO: figure out how to make this overridable at any granularity.
-        #       it should be possible with the DOM module now.
         description = ''
           Representations of the document in different formats
         '';