--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/implab/log/trace.js	Thu Dec 07 19:19:29 2017 +0300
@@ -0,0 +1,116 @@
+define(["../text/format"], function (format) {
+    'use strict';
+
+    var listeners = [];
+    var channels = {};
+
+    var Trace = function (name) {
+        this.name = name;
+        this._subscribers = [];
+    };
+
+    Trace.prototype.debug = function () {
+        if (Trace.level >= 4)
+            this.notify("debug", format.apply(null, arguments));
+    };
+
+    Trace.prototype.log = function () {
+        if (Trace.level >= 3)
+            this.notify("log", format.apply(null, arguments));
+    };
+
+    Trace.prototype.warn = function () {
+        if (Trace.level >= 2)
+            this.notify("warn", format.apply(null, arguments));
+
+    };
+
+    Trace.prototype.error = function () {
+        if (Trace.level >= 1)
+            this.notify("error", format.apply(null, arguments));
+    };
+
+    Trace.prototype.notify = function (name, msg) {
+        var me = this;
+        me._subscribers.forEach(function (cb) {
+            cb(me, name, msg);
+        });
+    };
+
+    Trace.prototype.subscribe = function (cb) {
+        this._subscribers.push(cb);
+    };
+
+    Trace.prototype.toString = function () {
+        return this.name;
+    };
+
+    Trace.createChannel = function (type, name, cb) {
+        var chId = name;
+        if (channels[chId])
+            return channels[chId];
+
+        var channel = new type(chId);
+        channels[chId] = channel;
+
+        Trace._onNewChannel(chId, channel);
+        cb(channel);
+    };
+
+    Trace._onNewChannel = function (chId, ch) {
+        listeners.forEach(function (listener) {
+            listener(chId, ch);
+        });
+    };
+
+    Trace.on = function (filter, cb) {
+        if (arguments.length == 1) {
+            cb = filter;
+            filter = undefined;
+        }
+        var d, test;
+        if (filter instanceof RegExp) {
+            test = function (chId) {
+                return filter.test(chId);
+            };
+        } else if (filter instanceof Function) {
+            test = filter;
+        } else if (filter) {
+            test = function (chId) {
+                return chId == filter;
+            };
+        }
+
+        if (test) {
+            d = function(chId, ch) {
+                if(test(chId))
+                    ch.subscribe(cb);
+            };
+        } else {
+            d = function(chId, ch) {
+                ch.subscribe(cb);
+            };
+        }
+        listeners.push(d);
+
+        for(var chId in channels)
+            d(chId,channels[chId]);
+    };
+
+    Trace.load = function (id, require, cb) {
+        if (id)
+            Trace.createChannel(Trace, id, cb);
+        else if (require.module && require.module.mid)
+            Trace.createChannel(Trace, require.module.mid, cb);
+        else
+            require(['module'], function (module) {
+                Trace.createChannel(Trace, module && module.id, cb);
+            });
+    };
+
+    Trace.dynamic = true;
+
+    Trace.level = 4;
+
+    return Trace;
+});
\ No newline at end of file