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Name resolution rules in PHP determine how the interpreter resolves and accesses different types of names such as variables, functions, classes, and namespaces. The process follows a set of predefined rules to determine the scope and context of each name.

Here are the main components and examples of PHP's name resolution rules:

1. Variable Scope:
- Local Scope: Variables declared inside a function are local scoped and can only be accessed within that function.

php
function myFunction() {
$x = 10; // Local variable
echo $x;
}
myFunction(); // Output: 10
echo $x; // Error: Undefined variable


- Global Scope: Variables declared outside of any function or class have global scope and can be accessed from anywhere in the script.

php
$x = 10; // Global variable
function myFunction() {
global $x;
echo $x;
}
myFunction(); // Output: 10
echo $x; // Output: 10


2. Function and Class Resolution:
- Functions: PHP follows a linear search path to resolve functions. It starts at the current namespace and then checks the global namespace if the function is not found.

php
function myFunction() {
echo "Hello";
}
myFunction(); // Output: Hello


- Classes: PHP resolves class names based on the current namespace and the use statements. If the class is not found, it appends the global namespace as a prefix to the class name.

php
namespace MyNamespace;

use OtherNamespace\SomeClass;

class MyClass {}

$obj = new MyClass(); // Resolves to 'MyNamespace\MyClass'
$obj2 = new SomeClass(); // Resolves to 'OtherNamespace\SomeClass'
$obj3 = new \GlobalClass(); // Resolves to 'GlobalClass'


These are simplified explanations and examples of PHP's name resolution rules. It's important to refer to the official PHP documentation for more comprehensive information on namespaces, class autoloading, and scoping rules in specific scenarios.