diff --git a/dingus/dingus.js b/dingus/dingus.js
index 021db5c..ec5b98a 100644
--- a/dingus/dingus.js
+++ b/dingus/dingus.js
@@ -7,60 +7,57 @@ let next_document = null;
 
 const STATUS = document.getElementById("status-line");
 
-function submit_grammar(code) {
-  if (pending_grammar) {
-    console.log("Grammar still pending, parking it");
-    next_grammar = code;
-  } else {
-    pending_grammar = code;
-    worker.postMessage({kind: "grammar_module", data: code});
-    console.log("Grammar posted");
-  }
-}
+const DOC_CHAINS = {};
+function chain_document_submit(kind, editor, on_success) {
+  let pending = null;
+  let next = null;
 
-function submit_document(code) {
-  if (pending_document) {
-    console.log("Document still pending, parking it");
-    next_document = code;
-  } else {
-    pending_document = code;
-    worker.postMessage({kind: "document", data: code});
-    console.log("Document posted");
+  function do_submit(document) {
+    if (pending) {
+      console.log("Old still pending, parking it...");
+      next = document;
+    } else {
+      pending = document;
+      worker.postMessage({kind, data: document});
+      console.log("Document submitted");
+    }
   }
+
+  function on_result(message) {
+    pending = null;
+    if (next) {
+      pending = next;
+      next = null;
+
+      worker.postMessage({kind, data: document});
+      console.log("Posted another document");
+    }
+    if (message.kind === "ok" && on_success) {
+      on_success(message);
+    }
+  }
+  DOC_CHAINS[kind] = on_result;
+
+  let change_timer_id = null;
+  editor.doc.on("change", () => {
+    clearTimeout(change_timer_id);
+    change_timer_id = setTimeout(() => {
+      change_timer_id = null;
+      do_submit(editor.doc.getValue());
+    }, 100);
+  });
 }
 
 const worker = new Worker('worker.js');
 worker.onmessage = (e) => {
   const message = e.data;
-  if (message.kind === "grammar_status") {
-    STATUS.innerText = message.message;
 
-    if ((message.status === "ok") || (message.status === "error")) {
-      pending_grammar = null;
-      if (next_grammar) {
-        pending_grammar = next_grammar;
-        next_grammar = null;
-
-        worker.postMessage({kind: "grammar_module", data: pending_grammar});
-        console.log("Posted another grammar");
-      }
-    }
+  const chain = DOC_CHAINS[message.kind];
+  if (chain) {
+    chain(message);
   }
 
-  if (message.kind === "doc_status") {
-    STATUS.innerText = message.message;
-
-    if ((message.status === "ok") || (message.status === "error")) {
-      pending_document = null;
-      if (next_document) {
-        pending_document = next_document;
-        next_document = null;
-
-        worker.postMessage({kind: "document", data: pending_document});
-        console.log("Posted another document");
-      }
-    }
-  }
+  STATUS.innerText = message.message;
 };
 
 
@@ -73,15 +70,7 @@ function setup_editors() {
       value: "from parser import Grammar\n\nclass MyGrammar(Grammar):\n    pass\n",
     },
   );
-
-  let grammar_change_timer_id = null;
-  grammar_editor.doc.on("change", () => {
-    clearTimeout(grammar_change_timer_id);
-    grammar_change_timer_id = setTimeout(() => {
-      grammar_change_timer_id = null;
-      submit_grammar(grammar_editor.doc.getValue());
-    }, 100);
-  });
+  chain_document_submit("grammar", grammar_editor);
 
   const input_editor = CodeMirror.fromTextArea(
     document.getElementById("input"),
@@ -89,15 +78,7 @@ function setup_editors() {
       lineNumbers: true,
     },
   );
-
-  let input_change_timer_id = null;
-  input_editor.doc.on("change", () => {
-    clearTimeout(input_change_timer_id);
-    input_change_timer_id = setTimeout(() => {
-      input_change_timer_id = null;
-      submit_document(input_editor.doc.getValue());
-    }, 100);
-  });
+  chain_document_submit("input", input_editor);
 }
 
 setup_editors();
diff --git a/dingus/worker.js b/dingus/worker.js
index ca82973..9b30b29 100644
--- a/dingus/worker.js
+++ b/dingus/worker.js
@@ -22,18 +22,18 @@ function data_to_js(thing) {
 const dingus_module = {
   post_grammar_status: function (message) {
     console.log("Grammar Status:", message);
-    postMessage({kind: "grammar_status", status: "loading", message});
+    postMessage({kind: "grammar", status: "loading", message});
   },
 
   post_grammar_loaded: function (name) {
     const msg = "Grammar '" + name + "' loaded";
     console.log(msg);
-    postMessage({kind: "grammar_status", status: "ok", message: msg});
+    postMessage({kind: "grammar", status: "ok", message: msg});
   },
 
   post_grammar_error: function(error) {
     console.log("Grammar Error:", error);
-    postMessage({kind:"grammar_status", status: "error", message: error});
+    postMessage({kind:"grammar", status: "error", message: error});
   },
 
   post_doc_parse: function(tree, errors) {
@@ -42,7 +42,7 @@ const dingus_module = {
 
     console.log("Doc parse:", tree, errors);
     postMessage({
-      kind: "doc_status",
+      kind: "input",
       status: "ok",
       message: "Parsed",
       errors: errors,
@@ -52,7 +52,7 @@ const dingus_module = {
 
   post_doc_error: function(error) {
     console.log("Doc Error:", error);
-    postMessage({kind:"doc_status", status: "error", message: error});
+    postMessage({kind:"input", status: "error", message: error});
   },
 };
 
@@ -182,9 +182,9 @@ self.onmessage = async function(event) {
 
   try {
     const { kind, data } = event.data;
-    if (kind === "grammar_module") {
+    if (kind === "grammar") {
       await load_grammar_module(data);
-    } else if (kind === "document") {
+    } else if (kind === "input") {
       await parse_document(data);
     }
   } catch (e) {