Should PHP developers always specify the data type when declaring variables, especially in functions that handle specific object types like mysqli?

It is good practice for PHP developers to specify the data type when declaring variables, especially in functions that handle specific object types like mysqli. This helps to ensure type safety and avoid unexpected errors or inconsistencies in the code. By specifying the data type, developers can clearly communicate the intended use of the variable and make the code more readable and maintainable.

// Example of specifying data types when declaring variables in PHP

// Declare a variable with specified data type
$stringVariable = "Hello World"; // string data type
$intVariable = 42; // integer data type
$floatVariable = 3.14; // float data type

// Function that handles mysqli object with specified data type
function fetchData(mysqli $connection, $query) {
    // Function implementation here
}