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/* within a class, def, trait or object, but not a constructor */ synchronized { /* code to run when an intrisctic lock on `this` is acquired */ /* no other thread can get the this lock unless execution is suspended with * `wait` on `this` */ }

The GetParentFolderName method returns the parent folder for any path. While this can also be used with folders, it is arguably more useful for extracting the path from an absolute file path: Dim fso As New Scripting.FileSystemObject Debug.Print fso.GetParentFolderName("C:\Users\Me\My Docume...

In some cases it is necessary to calculate a variable amount of values on separate Futures. Assume to have a List[Future[Int]], but instead a List[Int] needs to be processed. Then the question is how to turn this instance of List[Future[Int]] into a Future[List[Int]]. For this purpose there is the s...

Keeping a GUI responsive while running a lengthy process requires either some very elaborate "callbacks" to allow the GUI to process its message queue, or the use of (background) (worker) threads. Kicking off any number of threads to do some work usually isn't a problem. The fun starts wh...

Start with importing the library. from amqpstorm import Connection When consuming messages, we first need to define a function to handle the incoming messages. This can be any callable function, and has to take a message object, or a message tuple (depending on the to_tuple parameter defined in ...

Start with importing the library. from amqpstorm import Connection from amqpstorm import Message Next we need to open a connection to the RabbitMQ server. connection = Connection('127.0.0.1', 'guest', 'guest') After that we need to set up a channel. Each connection can have multiple channel...

PostgreSQL is an actively developed and mature open source database. Using the psycopg2 module, we can execute queries on the database. Installation using pip pip install psycopg2 Basic usage Lets assume we have a table my_table in the database my_database defined as follows. idfirst_namelast_n...

Following example shows steps involved in initializing a view from XIB. This is not a complex operation but exact steps need to be followed in order to do it right way first time, avoiding exceptions. How does loadNibNamed Works Main steps are: Create XIB Create class .h and .m Define outlet...

The first thing to do when taking your Meteor app offline is to create some visual indication of whether the local client app is connected to the server or not. There are lots of ways to do this, but the simplest way is to probably do something like this: Template.registerHelper('getOnlineStatus', ...

Finally, we want to get some of our dynamic data to be stored offline. meteor add ground:db Lists = new Meteor.Collection("lists"); GroundDB(Lists); Todos = new Meteor.Collection("todos") GroundDB(Todos);

The appcache will cause some confusion in your development workflow, because it hides Meteor's auto-updating features. When you turn off the server component of your app, the client portion in your browser will continue working. This is a good thing! But, you don't get the immediate feedback that ...

The first step to logging is simply to run Meteor from the shell, and you'll get the server logs in the command console. meteor The next step is to pipe the contents of std_out and std_err to a logfile, like so: meteor > my_app_log.log 2> my_app_err.log

Once you have both your server-side logging running, and your client side development tools, you can start looking at Meteor specific extensions like the Meteor Chrome DevTools Extension. This lets you actually observe server logging in the client! Because the database is everywhere. As is logging. ...

The following example is from 0.5 - 0.7 days, and illustrates how to log an error when the database hasn't populated the client side cursor yet. Template.landingPage.postsList = function(){ try{ return Posts.find(); }catch(error){ //color code the error (red) console.error(erro...

The following uses the Chrome Logging API. If the .group() syntax is used in multiple templates, it will graphically organize the console logs from different templates into a hierarchical tree. You can also see how to inspect the current data context, and how to stringify data. Template.landingPa...

Simple example of using the Chrome Logging API. Template.landingPage.events({ 'click .selectItemButton':function(){ // color code and count the user interaction (blue) console.count('click .selectItemButton'); } });

Logging can often clutter up the console, so it's common to define log levels to control what detail of data is getting logged. A common pattern is to specify a log level variables. var DEBUG = false; var TRACE = false; Template.landingPage.events({ 'click .selectItemButton':function(){ ...

Some teams find that they want to leave console log statements in their code, but not have them display in production. They will override the logging functions if a variable isn't set (possibly an environment variable). Additionally, this may qualify as a security feature in some situations. if (...

This deployment guide assumes you're using an Ubuntu server, and are either self-hosting or using an Infrastructure as a Service (IaaS) provider, such as Amazon Web Services or Rackspace. Your Ubuntu server needs to be running a daemon for launching other apps, for which we recommend the Upstart ser...

One favored approach to deploying to a server is to use Git or GitHub. This basically involves logging into your server, moving to the directory you want to run your app from, then cloning your files directly from GitHub. You then build your app on the server. This approach ensures that platform spe...