Tutorial by Examples: al

These rules apply only if you use manual reference counting! You own any object you create By calling a method whose name begins with alloc, new, copy or mutableCopy. For example: NSObject *object1 = [[NSObject alloc] init]; NSObject *object2 = [NSObject new]; NSObject *object3 = [object2 ...

To install a new package, e.g. aeson: cabal install aeson

python-social-auth is a framework that simplifies the social authentication and authorization mechanism. It contains many social backends (Facebook, Twitter, Github, LinkedIn, etc.) INSTALL First we need to install the python-social-auth package with pip install python-social-auth or download ...

Synopsis A fully functional demo of Firebase v3 Web authentication viewable here. Sign in with Facebook, Github, Google, Twitter, password based, and anonymous accounts. The code, available on Github, is easy to read and follow and is well documented. The focus is on the fully functional authent...

It is common for company to set up it's own nuget server for distribution of packages across different teams. Go to Solution Explorer and click Right Mouse button then choose Manage NuGet Packages for Solution In window that opens click on Settings Click on + in top right corner the...

C++11 There are a number of different type traits that compare more general types. Is Integral: Evaluates as true for all integer types int, char, long, unsigned int etc. std::cout << std::is_integral<int>::value << "\n"; // Prints true. std::cout << std::is_in...

In order to start using Sequelize, you must first install the Sequelize package using the Node Package Manager (npm). Install sequelize module Add --save option to store module in package.json npm install sequelize Next, depending on which database system you wish to use with Sequelize, instal...

public string GetCustomerNamesCsv() { List<CustomerData> customerDataRecords = GetCustomerData(); // Returns a large number of records, say, 10000+ StringBuilder customerNamesCsv = new StringBuilder(); foreach (CustomerData record in customerDataRecords) { custom...

In most cases all data that is accessed by several threads should be initialized before the threads are created. This ensures that all threads start with a clear state and no race condition occurs. If this is not possible once_flag and call_once can be used #include <threads.h> #include &lt...

Probably the two most popular free implementations of Common Lisp are Clozure Common Lisp (CCL) and Steel Bank Common Lisp (SBCL). They are both available for a variety of platforms including Linux on x86-64 and Linux on ARM. CCL: http://ccl.clozure.com/download.html SBCL: http://www.sbcl.org/gett...

Constraint created as NSLayoutConstraint(item: myView, attribute: NSLayoutAttribute.Leading, relatedBy: NSLayoutRelation.Equal, toItem: view, attribute: NSLayoutAttribute.LeadingMargin, multiplier: 1.0, constant: 20.0) or, from math point of view: view.attribute * multiplier + constant ...

UML is a language. That means it has words and a syntax how to group the words of the language in order to make sentences, paragraphs and finally articles and essays. Like with human languages you can construct anything from blurb to artistic works. And unlike in human languages you use graphical el...

Anonymous functions can be used for functional programming. The main problem to solve is that there is no native way for anchoring a recursion, but this can still be implemented in a single line: if_ = @(bool, tf) tf{2-bool}(); This function accepts a boolean value and a cell array of two functi...

The Keep-Alive extension to HTTP/1.0 and the persistent connection feature of HTTP/1.1 provide long-lived HTTP sessions which allow multiple requests to be sent over the same TCP connection. In some cases this has been shown to result in an almost 50% speedup in latency times for HTML documents ...

Ordering directly on JSONField is not yet supported in Django. But it's possible via RawSQL using PostgreSQL functions for jsonb: from django.db.models.expressions import RawSQL RatebookDataEntry.objects.all().order_by(RawSQL("data->>%s", ("json_objects_key",))) This e...

Some examples for a window of size 3: ;; Naïve attempt: (loop for (first second third) on '(1 2 3 4 5) do (print (* first second third))) ;; prints 6 24 60 then Errors on (* 4 5 NIL) ;; We will try again and put our attempt into a function (defun loop-3-window1 (function list) (loop...

There are two PyCharm editions: Community and Professional. Both are downloadable from JetBrains website. Additionally, there is another edition, PyCharm Edu. JetBrains recommend this edition, if you are learning or teaching Programming with Python. The supported platforms are Windows, Linux and m...

A common thought pattern for inexperienced Java programmers is that exceptions are "a problem" or "a burden" and the best way to deal with this is catch them all1 as soon as possible. This leads to code like this: .... try { InputStream is = new FileInputStream(fileName);...

As a privileged user (root or sudo): Create scollector directory: mkdir /opt/scollector In the /opt/scollector directory, download the latest binary build from the bosun/scollector site, [http://bosun.org/scollector/][1] wget https://github.com/bosun-monitor/bosun/releases/download/"version...

Detailed instructions on getting datepicker set up or installed.