How to specify the type of function return value using PHP annotations?

Use PHP annotations to specify the type of function return value. You can use the @return annotation at the front of the function signature, followed by the expected type. This syntax aids code readability and type checking, improving code reliability.

Use PHP annotations to specify the type of function return value

PHP annotations are special comments used to add meta information to PHP code . Using annotations, you can specify the type of a function's return value, which helps code readability and type checking.

Syntax

To specify the type of a function return value, use the @return annotation at the very beginning of the function signature, followed by the desired type. For example:

/**
 * @return int
 */
function sum(int $a, int $b): int
{
    return $a + $b;
}

In this example, the function sum indicates that it will return an integer (int).

Practical Case

Consider the following code, which calculates the average of two numbers:

function average(int $a, int $b)
{
    return ($a + $b) / 2;
}

Using annotations, we can explicitly specify the function return value Type of:

/**
 * @return float
 */
function average(int $a, int $b): float
{
    return ($a + $b) / 2;
}

Now the compiler will know that function average returns a floating point number, thus enhancing the reliability and readability of your code.

Note:

Type annotations are only supported in PHP versions 7.1 or higher.

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