Category: 05. Functions

In PHP, any variable that can be accessed from anywhere in a PHP script is called as a global variable. If the variable is declared outside all the functions or classes in the script, it becomes a global variable. While global variables can be accessed directly outside a function, they aren’t automatically available inside a function.…

Scope can be defined as the range of availability a variable has to the program in which it is declared. PHP variables can be one of four scope types − Local Variables A variable declared in a function is considered local; that is, it can be referenced solely in that function. Any assignment outside of…

Arrow functions were introduced in PHP 7.4 version. Arrow functions provide a simpler and more concise syntax for writing anonymous functions. With PHP 7.4, a keyword “fn” has been introduced for defining arrow functions, instead of the conventional use of the “function” keyword. Example The following example demonstrates how you can use the arrow function…

What are Anonymous Functions? PHP allows defining anonymous functions. Normally, when we define a function in PHP, we usually provide it a name which is used to call the function whenever required. In contrast, an anonymous function is a function that doesn’t have any name specified at the time of definition. Such a function is also called closure or lambda…

PHP is widely regarded as a weakly typed language. In PHP, you need not declare the type of a variable before assigning it any value. The PHP parser tries to cast the variables into compatible type as far as possible. For example, if one of the values passed is a string representation of a number,…

In PHP, the scope of a variable is the context within which it is defined and accessible to the extent in which it is accessible. Generally, a simple sequential PHP script that doesn’t have any loop or a function etc., has a single scope. Any variable declared inside the “<?php” and “?>” tag is available…

PHP supports using “type hints” at the time of declaring variables in the function definition and properties or instance variables in a class. PHP is widely regarded as a weakly typed language. In PHP, you need not declare the type of a variable before assigning it any value. The PHP parser tries to cast the…

A recursive function is such a function that calls itself until a certain condition is satisfied. In PHP, it is possible to defines a recursive function. Calculation of Factorial using Recursion The most popular example of recursion is calculation of factorial. Mathematically factorial is defined as − It can be seen that we use factorial…

To a function in PHP, in addition to scalar types, arrays, and objects, you can also pass a function as one of its arguments. If a function is defined to accept another function as an argument, the passed function will be invoked inside it. PHP’s standard library has certain built-in functions of this type, where…

A PHP function can have an optional return statement as the last statement in its function body. Most of the built-in functions in PHP return a certain value. For example the strlen() function returns the length of a string. Similarly, a user defined function can also return a certain value. A function is an independent,…