Debug log helper. Never add a console.log to your code. This one also runs a stack trace to show where it got called from. Otherwise you'll just see the line in this gist as the source of the log message, and that isn't helpful since you want to see where the log call was made.

debugLog.js

var app = {
  debug: function(message, level) {
    // Default level for logs
    if (typeof level === 'undefined' || level === 'log') {
      level = 'info';
    }

    // If we have a console...
    if (typeof console === 'object' && typeof console.debug === 'function') {
      // ...and the requested log level exists
      if (typeof console[level] === 'function') {
        // Let's add some styling to the error log
        var messageStyle = "display: block; font-size: 1em; line-height: 1.6em;";
        var fileStyle = "font-size: 0.9em; opacity: 0.6;";

        // Create an error so we can run a stack trace. With that we
        // can see where in the code app.debug() is called from.
        // Firebug/etc will just show the line #15 in this file as the caller.
        var e = new Error('stack trace helper error');
        var stack = e.stack.split('\n');
        var file = stack[1].substr(stack[1].indexOf("http"), stack[1].length);

        // Log message, with styling
        console[level]("%c" + message + "%c" + file, messageStyle, fileStyle);
      } else {
        // Otherwise fall back to debug level
        console.debug(message);
      }
    }
  }
};

app.debug('This is your final notice!');
app.debug('You have been warned!', 'warn');