Tutorial by Examples: int

Unlike normal Rust references, raw pointers are allowed to take null values. use std::ptr; // Create a const NULL pointer let null_ptr: *const u16 = ptr::null(); // Create a mutable NULL pointer let mut_null_ptr: *mut u16 = ptr::null_mut();

Rust has a default formatter for pointer types that can be used for displaying pointers. use std::ptr; // Create some data, a raw pointer pointing to it and a null pointer let data: u32 = 42; let raw_ptr = &data as *const u32; let null_ptr = ptr::null() as *const u32; // the {:p} mappi...

There are quite a number situations where one has huge amounts of data and using which he has to classify an object in to one of several known classes. Consider the following situations: Banking: When a bank receives a request from a customer for a bankcard, the bank has to decide whether to issue...

Let's say we have 8 houses. We want to setup telephone lines between these houses. The edge between the houses represent the cost of setting line between two houses. Our task is to set up lines in such a way that all the houses are connected and the cost of setting up the whole connection is mini...

DBCC commands enable user to maintain space in database, clean caches, shrink databases and tables. Examples are: DBCC DROPCLEANBUFFERS Removes all clean buffers from the buffer pool, and columnstore objects from the columnstore object pool. DBCC FREEPROCCACHE -- or DBCC FREEPROCCACHE (0x06...

When called without arguments, Node.js starts a REPL (Read-Eval-Print-Loop) also known as the “Node shell”. At a command prompt type node. $ node > At the Node shell prompt > type "Hello World!" $ node > "Hello World!" 'Hello World!'

LocalTime is an immutable class and thread-safe, used to represent time, often viewed as hour-min-sec. Time is represented to nanosecond precision. For example, the value "13:45.30.123456789" can be stored in a LocalTime. This class does not store or represent a date or time-zone. Instead...

Polymorphism is one of the basic concepts in OOP (Object Oriented Programming). Main idea of the polymorphism is that an object have the ability to take on different forms. To achieve that (polymorphism), we have two main approaches. Method overloading Occures when there are two or more meth...

Abstraction is one of the main concepts in Object Oriented Programming (OOP). This is the process of hiding the implementation details for the outsiders while showing only essential details. In another words, Abstraction is a technique to arrange the complexity of a program. There are two basic typ...

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Once you've connected to your mailbox, you'll want to take a look inside. The first useful command is imap_list. The first parameter is the resource you acquired from imap_open, the second is your mailbox string and the third is a fuzzy search string (* is used to match any pattern). $folders = ima...

You can return a list of all the messages in a mailbox using imap_headers. <?php $headers = imap_headers($mailbox); The result is an array of strings with the following pattern: [FLAG] [MESSAGE-ID])[DD-MM-YYY] [FROM ADDRESS] [SUBJECT TRUNCATED TO 25 CHAR] ([SIZE] chars) Here's a sample o...

Class is the piece of code where we define the attributes and/or behaviors of an object. You can define variables, constants, methods and constructors to the object, inside the class. In another words, class is the blueprint of an object. Let's see a sample class in Java, which defines a (simple) C...

Object is the base module in the Object Oriented Programming (OOP). An Object can be a variable, data structure (like an array, map, etc), or even a function or method. In OOP, we model real world objects like animals, vehicles, etc. An object can be defined in a class, which can be defined as the ...

this can also be cv-qualified, the same as any other pointer. However, due to the this parameter not being listed in the parameter list, special syntax is required for this; the cv-qualifiers are listed after the parameter list, but before the function's body. struct ThisCVQ { void no_qualifi...

C++11 Similarly to this cv-qualifiers, we can also apply ref-qualifiers to *this. Ref-qualifiers are used to choose between normal and rvalue reference semantics, allowing the compiler to use either copy or move semantics depending on which are more appropriate, and are applied to *this instead of...

The BigInteger class has a constructor dedicated to generate random BigIntegers, given an instance of java.util.Random and an int that specifies how many bits will the BigInteger have. Its usage is quite simple - when you call the constructor BigInteger(int, Random) like this: BigInteger randomBigI...

By utilizing the pre_save we can determine if a save action on our database was about updating an existing object or creating a new one. In order to achieve this you can check the state of the model object: @receiver(pre_save, sender=User) def pre_save_user(sender, instance, **kwargs): ...

Objective-C Add the delegate and a text-formatter to the ViewController.h file @interface ViewController : UIViewController <UIPrintInteractionControllerDelegate> { UISimpleTextPrintFormatter *_textFormatter; } In the ViewController.m file define the following constants #define Def...

An example of a constraint as expressed in the C standard is having two variables of the same name declared in a scope1), for example: void foo(int bar) { int var; double var; } This code breaches the constraint and must produce a diagnostic message at compile time. This is very usef...