Tutorial by Examples: class

The elapsedMillis library provides a class with the same name that keeps track of the time that passed since it was created or set to a certain value: #include <elapsedMillis.h> #define OUTPIN LED_BUILTIN #define PERIOD 500 elapsedMillis ledTime; bool ledState = false; void setup...

This test class will test the IsBlank(...) method of SomeClass. Below is the example SomeClass. This class has only the one, basic static method, but you will be unable to deploy it to a production instance for use until you have reached the code coverage threshold. public class SomeClass { ...

How to create User Model Class namespace App\Model\Table; use Cake\ORM\Table; class UsersTable extends Table { public function initialize(array $config) { $this->table('users'); //define table name $this->displayField('username'); // unique or other special field of...

You can use Modules to build more complex classes through composition. The include ModuleName directive incorporates a module's methods into a class. module Foo def foo_method puts 'foo_method called!' end end module Bar def bar_method puts 'bar_method called!' end end ...

Assume you want to delegate to a class but you do not want to provide the delegated-to class in the constructor parameter. Instead, you want to construct it privately, making the constructor caller unaware of it. At first this might seem impossible because class delegation allows to delegate only to...

Person = Struct.new :name do def greet(someone) "Hello #{someone}! I am #{name}!" end end Person.new('Alice').greet 'Bob' # => "Hello Bob! I am Alice!"

All objects are instances of a class. However, that is not the whole truth. In Ruby, every object also has a somewhat hidden singleton class. This is what allows methods to be defined on individual objects. The singleton class sits between the object itself and its actual class, so all methods defi...

In SQL Server, there are two categories of triggers: DDL Triggers and DML Triggers. DDL Triggers are fired in response to Data Definition Language (DDL) events. These events primarily correspond to Transact-SQL statements that start with the keywords CREATE, ALTER and DROP. DML Triggers are fired ...

A singleton is a pattern that restricts the instantiation of a class to one instance/object. For more info on python singleton design patterns, see here. class Singleton: def __new__(cls): try: it = cls.__it__ except AttributeError: it = cls.__it__ =...

Typed holes can make it easier to define functions, through an interactive process. Say you want to define a class instance Foo Bar (for your custom Bar type, in order to use it with some polymorphic library function that requires a Foo instance). You would now traditionally look up the documentati...

POSIX character classes are predefined sequences for a certain set of characters. Character classDescription[:alpha:]Alphabetic characters[:alnum:]Alphabetic characters and digits[:digit:]Digits[:xdigit:]Hexadecimal digits[:blank:]Space and Tab[:cntrl:]Control characters[:graph:]Visible characters ...

Unnamed struct is allowed (type has no name) void foo() { struct /* No name */ { float x; float y; } point; point.x = 42; } or struct Circle { struct /* No name */ { float x; float y; } center; // but a member name float...

Most KVO and KVC functionality is already implemented by default on all NSObject subclasses. To start observing a property named firstName of an object named personObject do this in the observing class: [personObject addObserver:self forKeyPath:@"firstName" ...

Sometimes it may be useful to have a specific asBoolean definition in your own program for some kind of objects. /** an oversimplified robot controller */ class RunController { def complexCondition int position = 0 def asBoolean() { return complexCondition(this...

Classes and modules have the same methods for introspecting instance variables as any other object. Class and modules also have similar methods for querying the class variables (@@these_things): p Module.methods.grep(/class_variable/) #=> [:class_variables, :class_variable_get, :remove_class_va...

Partial classes provide a clean way to separate core logic of your scripts from platform specific methods. Partial classes and methods are marked with the keyword partial. This signals the compiler to leave the class "open" and look in other files for the rest of the implementation. // E...

CoffeeScript provides a basic class structure that allows you to name your class, set the superclass, assign prototypal properties, and define the constructor, in a single assignable expression. Small example below: class Animal constructor: (@name) -> move: (meters) -> alert @n...

Less doesn't put any restrictions on the number of times the parent selector (&) can be used in a complex selector and so, we can use it more than once like in the below examples to select sibling elements without the need to repeat the selector. .demo { border: 1px solid black; /* add borde...

Introduces the definition of a class type. class foo { int x; public: int get_x(); void set_x(int new_x); }; Introduces an elaborated type specifier, which specifies that the following name is the name of a class type. If the class name has been declared already, it ca...

The following class can be used as a single class that can handle GET, POST, PUT, PATCH, and other requests: class APIResponseObject{ int responseCode; String response; APIResponseObject(int responseCode,String response) { this.responseCode = responseCode; ...