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Design patterns are a good way to keep your code readable and DRY. DRY stands for don't repeat yourself. Below you could find more examples about the most important design patterns. In software engineering, a software design pattern is a general reusable solution to a commonly occurring proble...

To install package simply run: install.packages("stringi") to load it: require("stringi")

A function is basically a named block of code. When you call the function name, the script block within that function runs. It is a list of PowerShell statements that has a name that you assign. When you run a function, you type the function name.It is a method of saving time when tackling repetitiv...

Serial.begin(speed) // Opens the serial port on the given baud rate Serial.begin(speed, config) Serial[1-3].begin(speed) // Arduino Mega only! When writing 1-3 it means you can choose between the numbers 1 to 3 when choosing the serial port. Serial[1-3].begin(speed, config) // Arduino Mega onl...

This extension filters data by either validating or sanitizing it. This is especially useful when the data source contains unknown (or foreign) data, like user supplied input. For example, this data may come from an HTML form. mixed filter_var ( mixed $variable [, int $filter = FILTER_DEFAULT ...

Regular Expressions (sometimes called regexs or regexps) are a textual syntax which represents the patterns which can be matched in the strings operated upon. Regular Expressions, introduced in c++11, may optionally support a return array of matched strings or another textual syntax defining how to...

insert(document or array of documents) insertOne( 'document', { writeConcern: 'document' } ) insertMany( { [ document 1 , document 2, ... ] }, { writeConcern: document, ordered: boolean } ) find(query, projection) findOne(query, projection) update(query, update) updateOne( query,...

define ( string $name , mixed $value [, bool $case_insensitive = false ] ) const CONSTANT_NAME = VALUE; Constants are used to store the values that are not supposed to be changed later. They also are often used to store the configuration parameters especially those which define the environ...

Recursion needs a stop condition stopCondition in order to exit the recursion. The original variable must be passed on to the recursive function so it becomes stored.

The general idea behind Dependency Injection is that you design your application around loosely coupled components while adhering to the Dependency Inversion Principle. By not depending on concrete implementations, allows to design highly flexible systems. The basic idea behind dependency inje...

virtual void f(); virtual void g() = 0; // C++11 or later: virtual void h() override; void i() override; virtual void j() final; void k() final; Only non-static, non-template member functions can be virtual. If you are using C++11 or later, it is recommended to use ...

JSONField(**options) Django's JSONField actually stores the data in a Postgres JSONB column, which is only available in Postgres 9.4 and later. JSONField is great when you want a more flexible schema. For example if you want to change the keys without having to do any data migratio...

In Component(s): props is an array of string literals or object references used to pass data from parent component. It can also be in object form when it is desired to have more fine grained control like specifying default values, type of data accepted, whether it is required or optional data h...

Quaternion.LookRotation(Vector3 forward [, Vector3 up]); Quaternion.AngleAxis(float angles, Vector3 axisOfRotation); float angleBetween = Quaternion.Angle(Quaternion rotation1, Quaternion rotation2);

Errors detected during execution are called exceptions and are not unconditionally fatal. Most exceptions are not handled by programs; it is possible to write programs that handle selected exceptions. There are specific features in Python to deal with exceptions and exception logic. Furthermore, exc...