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ParameterDetailscompletionHandlerA block that has no return value and takes the following parameters:accountStatusThe status of the current user’s iCloud account.errorAn error object or nil if the status is determined successfully. Use the information in the error object to determine whether the pr...

The much beloved ALTER statement. Changes the target of a GO TO paragraph. No longer part of the COBOL standard, still supported by many compilers for reasons of backward compatibility. (The syntax diagram is dimmed to show that this is no longer standard COBOL).

There are some means to chain commands together. Simple ones like just a ; or more complex ones like logical chains which run depending on some conditions. The third one is piping commands, which effectively hands over the output data to the next command in the chain.

The CANCEL statement ensures that a referenced program will be in an initial state the next time it is called, and to unload any resources for the module.

The COBOL CALL statement provides access to compiled library routines.

$dispatcher->dispatch(string $eventName, Event $event); $dispatcher->addListener(string $eventName, callable $listener, int $priority = 0); $dispatcher->addSubscriber(EventSubscriberInterface $subscriber); It is often best to use a single instance of EventDispatcher in your app...

Union types are used in several languages, notably C-language, to contain several different types which can "overlap" in the same memory space. In other words, they might contain different fields all of which start at the same memory offset, even when they might have different lengths an...

This example has a datepicker for the 'Start Date', an input for the 'Duration' (in weeks) and a second datepicker that is disabled for user input as it is updated on change of either the first datepicker or the duration inputs.

UIDatePicker does not inherit from UIPickerView, but it manages a custom picker-view object as a subview.

Excel VBA comes with a comprehensive object model which contains classes and objects that you can use to manipulate any part of the running Excel application. One of the most common objects you'll use is the Application object. This is a top-level catchall that represents the current running insta...

Splatting is a method of passing multiple parameters to a command as a single unit. This is done by storing the parameters and their values as key-value pairs in a hashtable and splatting it to a cmdlet using the splatting operator @. Splatting can make a command more readable and allows you to reu...

// Calling: variable.member_function(); variable_pointer->member_function(); // Definition: ret_type class_name::member_function() cv-qualifiers { body; } // Prototype: class class_name { virt-specifier ret_type member_function() cv-qualifiers virt-speci...

These are two sample programs that work together. One is a simple server, the other a simple client. Start the server in one window: python tserver.py Edit the server address in the client source file if desired. Then run python tclient.py The client connects to the server, then asks for i...