Why type awareness matters in PHP - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a variable with an integer type.

PHP

<?php
$number = [1];
?>

Drag options to blanks, or click blank then click option'

A42

B"42"

Ctrue

D3.14

Attempts:

3 left

💡 Hint

Common Mistakes

Using quotes around numbers makes them strings, not integers.

The variable $number should be assigned an integer value. The option 42 is an integer, while "42" is a string, true is a boolean, and 3.14 is a float.

2fill in blank

medium

Complete the code to declare a function that returns a string type.

PHP

<?php
function greet(): [1] {
    return "Hello!";
}
?>

Drag options to blanks, or click blank then click option'

Aint

Bfloat

Cbool

Dstring

Attempts:

3 left

💡 Hint

Common Mistakes

Using the wrong return type causes type errors.

The function greet returns a string, so the return type should be string. Other options represent different types.

3fill in blank

hard

Fix the error in the code by completing the type declaration for the parameter.

PHP

<?php
function doubleValue([1] $num): int {
    return $num * 2;
}
?>

Drag options to blanks, or click blank then click option'

Astring

Bbool

Cint

Dfloat

Attempts:

3 left

💡 Hint

Common Mistakes

Using string or bool causes type mismatch errors.

The function expects an integer parameter to multiply and return an integer. Declaring the parameter as int ensures type safety.

4fill in blank

hard

Fill both blanks to create an array with integer keys and string values.

PHP

<?php
$fruits = array([1] => [2]);
?>

Drag options to blanks, or click blank then click option'

A1

B"apple"

C"banana"

Dtrue

Attempts:

3 left

💡 Hint

Common Mistakes

Using boolean values as keys or values causes unexpected behavior.

The array key should be an integer 1, and the value should be a string like "apple". Other options are either wrong types or values.

5fill in blank

hard

Fill all three blanks to declare a typed class property and assign it a value.

PHP

<?php
class Person {
    public [1] $name = [2];
    public [3] $age = 30;
}
?>

Drag options to blanks, or click blank then click option'

Astring

B"John"

Cint

Dbool

Attempts:

3 left

💡 Hint

Common Mistakes

Assigning a string value to an integer property or vice versa.

The property $name is a string and should be assigned a string value like "John". The property $age is an integer type.