merge new :let and :unlet commands and support for <Leader> in mappings

chrome/content/vimperator/vimperator.js

@@ -359,6 +359,78 @@ const vimperator = (function() //{{{
             return new LocalFile(path, mode, perms, tmp);
         },
 
+        // partial sixth level expression evaluation
+        eval: function(string)
+        {
+            string = string.toString().replace(/^\s*/, "").replace(/\s*$/, "");
+            var match = string.match(/^&(\w+)/);
+            if (match)
+            {
+                var opt = this.options.get(match[1]);
+                if (!opt)
+                {
+                    this.echoerr("E113: Unknown option: " + match[1]);
+                    return;
+                }
+                var type = opt.type;
+                var value = opt.getter();
+                if (type != "boolean" && type != "number")
+                    value = value.toString();
+                return value;
+            }
+
+            // String
+            else if (match = string.match(/^(['"])([^\1]*?[^\\]?)\1/))
+            {
+                if (match)
+                    return match[2].toString();
+                else
+                {
+                    this.echoerr("E115: Missing quote: " + string);
+                    return;
+                }
+            }
+
+            // Number
+            else if (match = string.match(/^(\d+)$/))
+            {
+                return parseInt(match[1]);
+            }
+
+            var reference = this.variableReference(string);
+            if (!reference[0])
+                this.echoerr("E121: Undefined variable: " + string);
+            else
+                return reference[0][reference[1]];
+
+            return;
+        },
+
+        variableReference: function(string)
+        {
+            if (!string)
+                return [null, null, null];
+
+            if (match = string.match(/^([bwtglsv]):(\w+)/)) // Variable
+            {
+                // Other variables should be implemented
+                if (match[1] == "g")
+                {
+                    if (match[2] in this.globalVariables)
+                        return [this.globalVariables, match[2], match[1]];
+                    else
+                        return [null, match[2], match[1]];
+                }
+            }
+            else // Global variable
+            {
+                if (string in this.globalVariables)
+                    return [this.globalVariables, string, "g"];
+                else
+                    return [null, string, "g"];
+            }
+        },
+
         // logs a message to the javascript error console
         log: function(msg, level)
         {
@@ -383,10 +455,10 @@ const vimperator = (function() //{{{
                 }
                 catch (e)
                 {
-                    value = '';
+                    value = "";
                 }
 
-                string += i + ': ' + value + '\n';
+                string += i + ": " + value + "\n";
             }
             vimperator.log(string, level);
         },
@@ -623,6 +695,8 @@ const vimperator = (function() //{{{
             vimperator.echo    = vimperator.commandline.echo;
             vimperator.echoerr = vimperator.commandline.echoErr;
 
+            vimperator.globalVariables = {};
+
             // TODO: move elsewhere
             vimperator.registerCallback("submit", vimperator.modes.EX, function(command) { vimperator.execute(command); } );
             vimperator.registerCallback("complete", vimperator.modes.EX, function(str) { return vimperator.completion.exTabCompletion(str); } );