diff --git a/lib/appenders/categoryFilter.js b/lib/appenders/categoryFilter.js
index 7a35624..f854f65 100644
--- a/lib/appenders/categoryFilter.js
+++ b/lib/appenders/categoryFilter.js
@@ -1,23 +1,19 @@
-var levels = require('../levels');
+"use strict";
 var log4js = require('../log4js');
 
-function contains(list, value) {
-    return list.indexOf(value) !== -1;
-}
-
 function categoryFilter (excludes, appender) {
-    if (typeof(excludes) === 'string') excludes = [excludes];
-    return function(logEvent) {
-        if (excludes.indexOf(logEvent.categoryName) === -1) {
-            appender(logEvent);
-        }
+  if (typeof(excludes) === 'string') excludes = [excludes];
+  return function(logEvent) {
+    if (excludes.indexOf(logEvent.categoryName) === -1) {
+      appender(logEvent);
     }
+  };
 }
 
 function configure(config) {
-    log4js.loadAppender(config.appender.type);
-    var appender = log4js.appenderMakers[config.appender.type](config.appender);
-    return categoryFilter(config.exclude, appender);
+  log4js.loadAppender(config.appender.type);
+  var appender = log4js.appenderMakers[config.appender.type](config.appender);
+  return categoryFilter(config.exclude, appender);
 }
 
 exports.appender = categoryFilter;
diff --git a/test/categoryFilter-test.js b/test/categoryFilter-test.js
index 30dd42d..1ad10a0 100644
--- a/test/categoryFilter-test.js
+++ b/test/categoryFilter-test.js
@@ -5,75 +5,79 @@ var vows = require('vows')
 , assert = require('assert');
 
 function remove(filename) {
-    try {
-        fs.unlinkSync(filename);
-    } catch (e) {
-        //doesn't really matter if it failed
-    }
+  try {
+    fs.unlinkSync(filename);
+  } catch (e) {
+    //doesn't really matter if it failed
+  }
 }
 
 vows.describe('log4js categoryFilter').addBatch({
-    'appender': {
-        topic: function() {
-
-            var log4js = require('../lib/log4js'), logEvents = [], webLogger, appLogger;
-            log4js.clearAppenders();
-            var appender = require('../lib/appenders/categoryFilter').appender(['app'], function(evt) { logEvents.push(evt); });
-            log4js.addAppender(appender, ["app","web"]);
-
-            webLogger = log4js.getLogger("web");
-            appLogger = log4js.getLogger("app");
-
-            webLogger.debug('This should get logged');
-            appLogger.debug('This should not');
-            webLogger.debug('Hello again');
-            log4js.getLogger('db').debug('This shouldn\'t be included by the appender anyway');
-
-            return logEvents;
-        },
-        'should only pass matching category' : function(logEvents) {
-            assert.equal(logEvents.length, 2);
-            assert.equal(logEvents[0].data[0], 'This should get logged');
-            assert.equal(logEvents[1].data[0], 'Hello again');
-        }
+  'appender': {
+    topic: function() {
+      
+      var log4js = require('../lib/log4js'), logEvents = [], webLogger, appLogger;
+      log4js.clearAppenders();
+      var appender = require('../lib/appenders/categoryFilter')
+        .appender(
+          ['app'], 
+          function(evt) { logEvents.push(evt); }
+        );
+      log4js.addAppender(appender, ["app","web"]);
+      
+      webLogger = log4js.getLogger("web");
+      appLogger = log4js.getLogger("app");
+      
+      webLogger.debug('This should get logged');
+      appLogger.debug('This should not');
+      webLogger.debug('Hello again');
+      log4js.getLogger('db').debug('This shouldn\'t be included by the appender anyway');
+      
+      return logEvents;
     },
-
-    'configure': {
-        topic: function() {
-            var log4js = require('../lib/log4js')
-          , logger, weblogger;
-
-            remove(__dirname + '/categoryFilter-web.log');
-            remove(__dirname + '/categoryFilter-noweb.log');
-
-            log4js.configure('test/with-categoryFilter.json');
-            logger = log4js.getLogger("app");
-            weblogger = log4js.getLogger("web");
-
-            logger.info('Loading app');
-            logger.debug('Initialising indexes');
-            weblogger.info('00:00:00 GET / 200');
-            weblogger.warn('00:00:00 GET / 500');
-            //wait for the file system to catch up
-            setTimeout(this.callback, 100);
-        },
-        'tmp-tests.log': {
-            topic: function() {
-                fs.readFile(__dirname + '/categoryFilter-noweb.log', 'utf8', this.callback);
-            },
-            'should contain all log messages': function(contents) {
-                var messages = contents.trim().split('\n');
-                assert.deepEqual(messages, ['Loading app','Initialising indexes']);
-            }
-        },
-        'tmp-tests-web.log': {
-            topic: function() {
-                fs.readFile(__dirname + '/categoryFilter-web.log','utf8',this.callback);
-            },
-            'should contain only error and warning log messages': function(contents) {
-                var messages = contents.trim().split('\n');
-                assert.deepEqual(messages, ['00:00:00 GET / 200','00:00:00 GET / 500']);
-            }
-        }
+    'should only pass matching category' : function(logEvents) {
+      assert.equal(logEvents.length, 2);
+      assert.equal(logEvents[0].data[0], 'This should get logged');
+      assert.equal(logEvents[1].data[0], 'Hello again');
     }
+  },
+  
+  'configure': {
+    topic: function() {
+      var log4js = require('../lib/log4js')
+      , logger, weblogger;
+      
+      remove(__dirname + '/categoryFilter-web.log');
+      remove(__dirname + '/categoryFilter-noweb.log');
+      
+      log4js.configure('test/with-categoryFilter.json');
+      logger = log4js.getLogger("app");
+      weblogger = log4js.getLogger("web");
+      
+      logger.info('Loading app');
+      logger.debug('Initialising indexes');
+      weblogger.info('00:00:00 GET / 200');
+      weblogger.warn('00:00:00 GET / 500');
+      //wait for the file system to catch up
+      setTimeout(this.callback, 100);
+    },
+    'tmp-tests.log': {
+      topic: function() {
+        fs.readFile(__dirname + '/categoryFilter-noweb.log', 'utf8', this.callback);
+      },
+      'should contain all log messages': function(contents) {
+        var messages = contents.trim().split('\n');
+        assert.deepEqual(messages, ['Loading app','Initialising indexes']);
+      }
+    },
+    'tmp-tests-web.log': {
+      topic: function() {
+        fs.readFile(__dirname + '/categoryFilter-web.log','utf8',this.callback);
+      },
+      'should contain only error and warning log messages': function(contents) {
+        var messages = contents.trim().split('\n');
+        assert.deepEqual(messages, ['00:00:00 GET / 200','00:00:00 GET / 500']);
+      }
+    }
+  }
 }).export(module);