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do-notation is syntactic sugar for monads. Here are the rules: do x <- mx do x <- mx y <- my is equivalent to do y <- my ... ... do let a = b let a = b in ...

CoffeeScript allows to deconstruct objects and arrays when they are fed to functions as arguments. A function that leverages deconstruction will specify in its signature all the fields that are expected within its body. When invoking such function, an object or array containing all the expected fie...

The example below will collect the Device's OS version number and the the version of the application (which is defined in each projects' properties) that is entered into Version name on Android and Version on iOS. First make an interface in your PCL project: public interface INativeHelper { /...

Any public Sub, Function, or Property inside a class module can be called by preceding the call with an object reference: Object.Procedure In a DateRange class, a Sub could be used to add a number of days to the end date: Public Sub AddDays(ByVal NoDays As Integer) mEndDate = mEndDate + No...

Bootstrap requires a containing element to wrap site contents and house our grid system. You may choose one of two containers to use in your projects. Use .container class for a responsive fixed width container. <div class="container"> ... </div> Use .container-fluid c...

Swift UIApplication.sharedApplication().preferredContentSizeCategory Objective-C [UIApplication sharedApplication].preferredContentSizeCategory; This returns a content size category constant, or an accessibility content size category constant.

You can register for notifications of when the device text size is changed. Swift NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(updateFont), name: name:UIContentSizeCategoryDidChangeNotification, object: nil) Objective-C [[NSNotificationCenter defaultCenter] addObs...

$dbServer = "localhost,1234"; //Name of the server/instance, including optional port number (default is 1433) $dbName = "db001"; //Name of the database $dbUser = "user"; //Name of the user $dbPassword = "password"; //DB Password of that user $connectionI...

You have to create a different strings.xml file for every new language. Right-click on the res folder Choose New → Values resource file Select a locale from the available qualifiers Click on the Next button (>>) Select a language Name the file strings.xml strings.xml <resources&...

When first introduced, AsyncTasks were executed serially on a single background thread. Starting with DONUT, this was changed to a pool of threads allowing multiple tasks to operate in parallel. Starting with HONEYCOMB, tasks are executed on a single thread to avoid common application errors caused ...

You can use the following code for going back and forward. if (!function_exists('codepoint_encode')) { function codepoint_encode($str) { return substr(json_encode($str), 1, -1); } } if (!function_exists('codepoint_decode')) { function codepoint_decode($str) { re...

You can use the following code for going back and forward. if (!function_exists('mb_internal_encoding')) { function mb_internal_encoding($encoding = NULL) { return ($from_encoding === NULL) ? iconv_get_encoding() : iconv_set_encoding($encoding); } } if (!function_exists('mb_c...

Each resource directory under the res folder (listed in the example above) can have different variations of the contained resources in similarly named directory suffixed with different qualifier-values for each configuration-type. Example of variations of `` directory with different qualifier value...

C and C++ are well known as high-performance languages - largely due to the heavy amount of code customization, allowing a user to specify performance by choice of structure. When optimizing it is important to benchmark relevant code and completely understand how the code will be used. Common opti...

Optimizing by using the right data structures at the right time can change the time-complexity of the code. // This variant of stableUnique contains a complexity of N log(N) // N > number of elements in v // log(N) > insert complexity of std::set std::vector<std::string> stableUnique...

Save the session variable as a variable. $session = Yii::$app->session; $sess = $session['keys']; Then create or update the array value you want $sess['first'] = 'abc'; And finally save to the session variable $session['keys'] = $sess

When storing JSON documents in SQL Server, We need to be able to efficiently filter and sort query results on properties of the JSON documents. CREATE TABLE JsonTable ( id int identity primary key, jsonInfo nvarchar(max), CONSTRAINT [Content should be formatted as JSON] CHECK...

Creating a dictionary: set mydict [dict create a 1 b 2 c 3 d 4] dict get $mydict b ; # returns 2 set key c set myval [dict get $mydict $key] puts $myval # remove a value dict unset mydict b # set a new value dict set mydict e 5 Dictionary keys can be nested. dict set mycars mustang colo...

Synchronized modifier is used to control the access of a particular method or a block by multiple threads. Only one thread can enter into a method or a block which is declared as synchronized. synchronized keyword works on intrinsic lock of an object, in case of a synchronized method current objects...

This worked for me to move from Ubuntu 12.04 (Jenkins ver. 1.628) to Ubuntu 16.04 (Jenkins ver. 1.651.2). I first installed Jenkins from the repositories. Stop both Jenkins servers Copy JENKINS_HOME (e.g. /var/lib/jenkins) from the old server to the new one. From a console in the new serve...