repl: remove a unnecessary concatenation

lib/repl.js

@@ -247,7 +247,7 @@ function REPLServer(prompt, stream, eval_, useGlobal, ignoreUndefined) {
     // Check to see if a REPL keyword was used. If it returns true,
     // display next prompt and return.
     if (cmd && cmd.charAt(0) === '.' && isNaN(parseFloat(cmd))) {
-      var matches = cmd.match(/^(\.[^\s]+)\s*(.*)$/);
+      var matches = cmd.match(/^\.([^\s]+)\s*(.*)$/);
       var keyword = matches && matches[1];
       var rest = matches && matches[2];
       if (self.parseREPLKeyword(keyword, rest) === true) {
@@ -707,7 +707,7 @@ REPLServer.prototype.defineCommand = function(keyword, cmd) {
   } else if (!util.isFunction(cmd.action)) {
     throw new Error('bad argument, action must be a function');
   }
-  this.commands['.' + keyword] = cmd;
+  this.commands[keyword] = cmd;
 };
 
 REPLServer.prototype.memory = function memory(cmd) {