diff --git a/content/bookmarks.js b/content/bookmarks.js
index 7d1cc2c5..0334eca4 100644
--- a/content/bookmarks.js
+++ b/content/bookmarks.js
@@ -723,6 +723,8 @@ function History() //{{{
         function (args) { history.list(args.string, args.bang); },
         {
             bang: true,
+            literal: true,
+            completer: function (context) completion.history(context)
             // completer: function (filter) completion.history(filter)
         });
 
diff --git a/content/commands.js b/content/commands.js
index f5198318..5839d8cd 100644
--- a/content/commands.js
+++ b/content/commands.js
@@ -602,7 +602,7 @@ function Commands() //{{{
 
                 if (complete)
                 {
-                    if (argCount == "0" || args.length > 0  && (argCount == "1" || argCount == "?"))
+                    if (argCount == "0" || args.length > 0  && (/[1?]/.test(argCount)))
                         complete.highlight(i, sub.length, "SPELLCHECK")
                 }
 
@@ -639,9 +639,9 @@ function Commands() //{{{
                 if (complete)
                     args.completeArg = args.length - 1;
 
-                if (count <= 0)
-                    break;
                 i += count;
+                if (count <= 0 || i == str.length)
+                    break;
             }
 
             if (complete)
@@ -666,12 +666,14 @@ function Commands() //{{{
             }
 
             // check for correct number of arguments
-            if (!complete && (args.length == 0 && /^[1+]$/.test(argCount) ||
-                    // TODO: what is this for? -- djk
-                    literal && argCount == "+" && /^\s*$/.test(args.literalArg)))
+            if (args.length == 0 && /^[1+]$/.test(argCount) ||
+                    literal && argCount == "+" && /^\s*$/.test(args.literalArg))
             {
-                liberator.echoerr("E471: Argument required");
-                return null;
+                if (!complete)
+                {
+                    liberator.echoerr("E471: Argument required");
+                    return null;
+                }
             }
             else if (args.length == 1 && (argCount == "0") ||
                      args.length > 1  && /^[01?]$/.test(argCount))
diff --git a/content/completion.js b/content/completion.js
index 75b0a581..2998d86e 100644
--- a/content/completion.js
+++ b/content/completion.js
@@ -117,7 +117,6 @@ CompletionContext.prototype = {
                 return [];
             let prefix = self.value.substring(minStart, context.offset);
             return context.items.map(function makeItem(item) ({ text: prefix + item.text, item: item.item }));
-            //return [{ text: prefix + item.text, item: item.item } for ([i, item] in Iterator(context.items))];
         });
         return { start: minStart, items: util.Array.flatten(items), longestSubstring: this.longestAllSubstring }
     },
@@ -157,13 +156,16 @@ CompletionContext.prototype = {
     get completions() this._completions || [],
     set completions(items)
     {
+        // Accept a generator
+        if (!(items instanceof Array))
+            items = [x for (x in items)];
         delete this.cache.filtered;
         delete this.cache.filter;
         this.cache.rows = [];
         this.hasItems = items.length > 0;
         this._completions = items;
         let self = this;
-        if (this.updateAsync)
+        if (this.updateAsync && !this.noUpdate)
             liberator.callInMainThread(function () { self.onUpdate.call(self) });
     },
 
@@ -234,10 +236,9 @@ CompletionContext.prototype = {
         if (this.generate && !this.background)
         {
             // XXX
-            let updateAsync = this.updateAsync;
-            this.updateAsync = false;
+            this.noUpdate = true;
             this.completions = items = this.generate();
-            this.updateAsync = updateAsync;
+            this.noUpdate = false;
         }
         this.cache.filter = this.filter;
         if (items == null)
@@ -320,6 +321,7 @@ CompletionContext.prototype = {
         this.offset += count;
         if (this.quote)
         {
+            this.offset += this.quote[0].length;
             this.quote[0] = "";
             this.quote[2] = "";
         }
@@ -461,7 +463,6 @@ function Completion() //{{{
         let str = "";
 
         let lastIdx = 0;
-        let continuing = false;
 
         let cacheKey = null;
 
@@ -545,12 +546,11 @@ function Completion() //{{{
 
         this.eval = function eval(arg, key, tmp)
         {
-            if (!("eval" in this.context.cache))
+            if (!this.context.cache.eval)
                 this.context.cache.eval = {};
             let cache = this.context.cache.eval;
             if (!key)
                 key = arg;
-
             if (key in cache)
                 return cache[key];
 
@@ -608,23 +608,10 @@ function Completion() //{{{
                 return ret;
             }
 
-            let i = start, c = "";     /* Current index and character, respectively. */
+            let i = 0, c = "";     /* Current index and character, respectively. */
 
-            // We're starting afresh.
-            if (start == 0)
-            {
-                stack = [];
-                push("#root");
-            }
-            else
-            {
-                // A new statement may have been pushed onto the stack just after
-                // the end of the last string. We'll throw it away for now, and
-                // add it again later if it turns out to be valid.
-                let s = top[STATEMENTS];
-                if (s[s.length - 1] == start)
-                    s.pop();
-            }
+            stack = [];
+            push("#root");
 
             /* Build a parse stack, discarding entries as opening characters
              * match closing characters. The stack is walked from the top entry
@@ -704,20 +691,11 @@ function Completion() //{{{
             this.context = context;
             let string = context.filter;
 
-            context.process = [null, function highlight(item, v) template.highlight(v, true)];
-            context.compare = function ({item: {key: a}}, {item: {key: b}})
-            {
-                if (!isNaN(a) && !isNaN(b))
-                    return a - b;
-                return String.localeCompare(a, b);
-            }
-
             let self = this;
             try
             {
-                continuing = lastIdx && string.indexOf(str) == 0;
                 str = string;
-                buildStack.call(this, continuing ? lastIdx : 0);
+                buildStack.call(this);
             }
             catch (e)
             {
@@ -729,6 +707,9 @@ function Completion() //{{{
 
             /* Okay, have parse stack. Figure out what we're completing. */
 
+            if (/[\])}"';]/.test(str[lastIdx - 1]) && last != '"' && last != '"')
+                return;
+
             // Find any complete statements that we can eval before we eval our object.
             // This allows for things like: let doc = window.content.document; let elem = doc.createElement...; elem.<Tab>
             let prev = 0;
@@ -788,35 +769,50 @@ function Completion() //{{{
             function fill(context, obj, name, compl, anchored, key, last, offset)
             {
                 context.title = [name];
-                context.key = name;
                 context.anchored = anchored;
                 context.filter = key;
                 context.itemCache = context.parent.itemCache;
-                if (compl)
-                    context.completions = compl;
-                else
-                    context.generate = function () self.objectKeys(obj);
+                context.key = name;
 
                 if (last != undefined)
                     context.quote = [last, function (text) util.escapeString(text.substr(offset), ""), last];
                 else // We're not looking for a quoted string, so filter out anything that's not a valid identifier
                     context.filters.push(function (item) /^[\w$][\w\d$]*$/.test(item.text));
-                if (!anchored)
-                    context.filters.push(function (item) util.compareIgnoreCase(item.text.substr(0, key.length), key));
+
+                compl.call(self, context, obj);
             }
 
             function complete(objects, key, compl, string, last)
             {
+                let orig = compl;
+                if (!compl)
+                    compl = function (context, obj) {
+                        context.process = [null, function highlight(item, v) template.highlight(v, true)];
+                        if (!context.anchored)
+                            context.filters.push(function (item) util.compareIgnoreCase(item.text.substr(0, key.length), key));
+                        context.compare = function ({item: {key: a}}, {item: {key: b}})
+                        {
+                            if (!isNaN(a) && !isNaN(b))
+                                return a - b;
+                            return String.localeCompare(a, b);
+                        }
+                        context.generate = function () self.objectKeys(obj);
+                    }
+                let filter = key + (string || "");
                 for (let [,obj] in Iterator(objects))
                 {
-                    this.context.fork(obj[1], top[OFFSET], this, fill, obj[0], obj[1], compl,
-                        true, key + (string || ""), last, key.length);
+                    try {
+                    this.context.fork(obj[1], top[OFFSET], this, fill,
+                        obj[0], obj[1], compl, compl != orig, filter, last, key.length);
+                    } catch(e) { liberator.reportError(e) }
                 }
+                if (orig)
+                    return;
                 for (let [,obj] in Iterator(objects))
                 {
                     obj[1] += " (substrings)";
-                    this.context.fork(obj[1], top[OFFSET], this, fill, obj[0], obj[1], compl,
-                        false, key + (string || ""), last, key.length);
+                    this.context.fork(obj[1], top[OFFSET], this, fill,
+                        obj[0], obj[1], compl, false, filter, last, key.length);
                 }
             }
 
@@ -888,19 +884,22 @@ function Completion() //{{{
 
                     // Split up the arguments
                     let prev = get(-2)[OFFSET];
-                    let args = get(-2)[FULL_STATEMENTS].map(function splitArgs(s)
+                    let args = [];
+                    for (let [i, idx] in Iterator(get(-2)[FULL_STATEMENTS]))
                     {
-                        let ret = str.substring(prev + 1, s);
-                        prev = s;
-                        return ret;
-                    });
-                    args.push(key);
-
-                    let compl = completer.call(this, func, obj[0][0], string, args);
-                    if (!(compl instanceof Array))
-                        compl = [v for (v in compl)];
+                        let arg = str.substring(prev + 1, idx);
+                        prev = idx;
+                        args.__defineGetter__(i, function () self.eval(ret));
+                    }
                     key = this.eval(key);
-                    obj[0][1] += "." + func + "(...";
+                    args.push(key + string);
+
+                    compl = function (context, obj) {
+                        let res = completer.call(self, context, func, obj, args);
+                        if (res)
+                            context.completions = res;
+                    }
+                    obj[0][1] += "." + func + "(... [" + args.length + "]";
                     return complete.call(this, obj, key, compl, string, last);
                 }
 
@@ -935,20 +934,16 @@ function Completion() //{{{
 
     let self = {
 
-        // FIXME
-        get getKey() this._getKey || function (item, key) item[{ text: 0, description: 1, icon: 2 }[key]],
-        set getKey(getKey) this._getKey = getKey,
-
         setFunctionCompleter: function setFunctionCompleter(funcs, completers)
         {
             funcs = Array.concat(funcs);
             for (let [,func] in Iterator(funcs))
             {
-                func.liberatorCompleter = function liberatorCompleter(func, obj, string, args) {
+                func.liberatorCompleter = function liberatorCompleter(context, func, obj, args) {
                     let completer = completers[args.length - 1];
                     if (!completer)
                         return [];
-                    return completer.call(this, this.eval(obj), this.eval(args.pop()) + string, args);
+                    return completer.call(this, context, obj, args);
                 };
             }
         },
@@ -957,9 +952,7 @@ function Completion() //{{{
         _runCompleter: function _runCompleter(name, filter)
         {
             let context = CompletionContext(filter);
-            if (typeof name == "string")
-                name = this[name];
-            name.apply(this, [context].concat(Array.slice(arguments, 2)));
+            context.fork.apply(context, ["run", 0, this, name].concat(Array.slice(arguments, 2)));
             while (context.incomplete)
                 liberator.threadYield(true, true);
             return context.allItems;
@@ -1121,7 +1114,6 @@ function Completion() //{{{
                     text: [i + ": " + (tab.label || "(Untitled)"), i + ": " + url],
                     url:  url,
                     indicator: indicator,
-                    i: i,
                     icon: tab.image
                 };
             });
diff --git a/content/io.js b/content/io.js
index a5fcfb6c..f9324086 100644
--- a/content/io.js
+++ b/content/io.js
@@ -366,7 +366,10 @@ function IO() //{{{
     liberator.registerObserver("load_completion", function ()
     {
         completion.setFunctionCompleter([ioManager.getFile, ioManager.expandPath],
-            [function (obj, arg) completion.runCompleter("file", arg.replace(/[^\/]*$/, ""))]);
+            [function (context, obj, args) {
+                context.quote[2] = "";
+                completion.file(context, true);
+            }]);
     });
 
     var ioManager = {
diff --git a/content/liberator.js b/content/liberator.js
index 8e380205..05d18ca8 100644
--- a/content/liberator.js
+++ b/content/liberator.js
@@ -215,7 +215,7 @@ const liberator = (function () //{{{
             {
                 argCount: "1",
                 bang: true,
-                completer: function (context) completion.dialog(context)
+                completer: function (context, args) completion.dialog(context)
             });
 
         // TODO: move this
diff --git a/content/mappings.js b/content/mappings.js
index 3b848828..a43e8d39 100644
--- a/content/mappings.js
+++ b/content/mappings.js
@@ -263,9 +263,9 @@ function Mappings() //{{{
         completion.setFunctionCompleter(mappings.get,
         [
             null,
-            function (obj, filter, args)
+            function (context, obj, args)
             {
-                let mode = this.eval(args[0]);
+                let mode = args[0]
                 return util.Array.flatten(
                 [
                     [[name, map.description] for ([i, name] in Iterator(map.names))]
diff --git a/content/options.js b/content/options.js
index c0661ba8..ae1ca578 100644
--- a/content/options.js
+++ b/content/options.js
@@ -700,7 +700,7 @@ function Options() //{{{
                     context.title = ["Option"];
                     context.quote = [prefix, util.identity, ""];
                     context.keys = { text: "names", description: "description" };
-                    context.completions = [opt for (opt in opts)];
+                    context.completions = opts;
                     return;
                 }
                 else if (prefix == "no")