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In order to call a function through a function pointer, the function pointer's type must exactly match the function's type. Otherwise, the behaviour is undefined. Example: int f(); void (*p)() = reinterpret_cast<void(*)()>(f); p(); // undefined

To build up an expression like _ => _.Field == "VALUE" at runtime. Given a predicate _ => _.Field and a string value "VALUE", create an expression that tests whether or not the predicate is true. The expression is suitable for: IQueryable<T>, IEnumerable<T>...

Configuring the connection programmatically: var config = new ClientConfiguration { Servers = new List<Uri> { new Uri("http://localhost:8091/pools") }, BucketConfigs = new Dictionary<string, BucketConfiguration> ...

A spannable TextView can be used in Android to highlight a particular portion of text with a different color, style, size, and/or click event in a single TextView widget. Consider that you have defined a TextView as follows: TextView textview=findViewById(R.id.textview); Then you can apply diff...

To get versionName and versionCode of current build of your application you should query Android's package manager. try { // Reference to Android's package manager PackageManager packageManager = this.getPackageManager(); // Getting package info of this application PackageInfo...

To get the time at which your app was installed or updated, you should query Android's package manager. try { // Reference to Android's package manager PackageManager packageManager = this.getPackageManager(); // Getting package info of this application PackageInfo info = pack...

foreach is unusual among the collections iterators in that it does not return a result. Instead it applies a function to each element that has only side effects. For example: scala> val x = List(1,2,3) x: List[Int] = List(1, 2, 3) scala> x.foreach { println } 1 2 3 The function sup...

Since Yii2 version 2.0.4 there is the EachValidator used to validate each item in an array. [ // ... other rules ['userIDs', 'each', 'rule' => ['integer']], ] The ['integer'] part can be every other validator object that Yii2 offers and can hold the specific arguments for the valid...

System.assert can be used to check that a boolean expression evaluates to true: System.assert(Service.isActive()); System.assert(!Service.getItems().isEmpty(), 'items should not be empty'); System.assertEquals and System.assertNotEquals can be used to check equality of two values. The expected ...

class Example def example_method :example end def subexample_method :example end def not_missed_method :example end def method_missing name return :example if name == :missing_example_method return :example if name == :missing_subexample_method ...

Ruby moves up on ancestors chain of an object. This chain can contain both modules and classes. Same rules about moving up the chain apply to modules as well. class Example end module Prepended def initialize *args return super :default if args.empty? super end end module Fi...

There are two ways to interrupt messages. Use method_missing to interrupt any non defined message. Define a method in middle of a chain to intercept the message After interrupting messages, it is possible to: Reply to them. Send them somewhere else. Modify the message or its result. ...

The break operator will exit a program loop immediately. It can be used in For, ForEach, While and Do loops or in a Switch Statement. $i = 0 while ($i -lt 15) { $i++ if ($i -eq 7) {break} Write-Host $i } The above will count to 15 but stop as soon as 7 is reached. Note: When u...

Prior to Json.NET 4.5 dates were written using the Microsoft format: "/Date(1198908717056)/". If your server sends date in this format you can use the below code to serialize it to NSDate: Objective-C (NSDate*) getDateFromJSON:(NSString *)dateString { // Expect date in this format ...

This can be used in various chat applications, rss feeds, and social apps where you need to have latest feeds with timestamps: Objective-C - (NSString *)getHistoricTimeText:(NSDate *)since { NSString *str; NSTimeInterval interval = [[NSDate date] timeIntervalSinceDate:since]; if(in...

Using a file Swift let data = NSData(contentsOfFile: filePath) //assuming filePath is a valid path Objective-C NSData *data = [NSData dataWithContentsOfFile:filePath]; //assuming filePath is a valid path Using a String object Swift let data = (string as NSString).dataUsingEncoding(NSUTF8S...

To String Swift let string = String(NSString(data: data, encoding: NSUTF8StringEncoding)) //assuming data is a valid NSData object Objective-C NSString *string = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]; //assuming data is a valid NSData object [string release]; T...

This class is called Greeter. Its responsibility is to output a greeting. It has two dependencies. It needs something that will give it the greeting to output, and then it needs a way to output that greeting. Those dependencies are both described as interfaces, IGreetingProvider and IGreetingWriter....

This builds on the previous example of the Greeter class which has two dependencies, IGreetingProvider and IGreetingWriter. The actual implementation of IGreetingProvider might retrieve a string from an API call or a database. The implementation of IGreetingWriter might display the greeting in the ...

Dependency injection means writing classes so that they do not control their dependencies - instead, their dependencies are provided to them ("injected.") This is not the same thing as using a dependency injection framework (often called a "DI container", "IoC container&quo...