Constructor promotion in PHP - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a promoted property in the constructor.

PHP

<?php
class User {
    public function __construct(private [1] $name) {}
}

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

Aarray

Bstring

Cbool

Dint

Attempts:

3 left

💡 Hint

Common Mistakes

Using int or bool for a text property.

Omitting the type declaration.

The constructor promotion syntax requires the type before the property name. Here, string is the correct type for the $name property.

2fill in blank

medium

Complete the code to promote two properties in the constructor.

PHP

<?php
class Product {
    public function __construct(private string $name, private [1] $price) {}
}

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Afloat

Bstring

Cbool

Darray

Attempts:

3 left

💡 Hint

Common Mistakes

Using int which only holds whole numbers.

Using string for numeric values.

The $price property should hold decimal numbers, so float is the correct type.

3fill in blank

hard

Fix the error in the constructor promotion syntax.

PHP

<?php
class Order {
    public function __construct(private [1] $id, private int $quantity) {}
}

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

Aint

Bbool

Cstring

Dfloat

Attempts:

3 left

💡 Hint

Common Mistakes

Using string for numeric IDs.

Omitting the type declaration.

The $id property should be an integer, so int is the correct type to fix the error.

4fill in blank

hard

Fill both blanks to promote properties with correct types.

PHP

<?php
class Employee {
    public function __construct(private [1] $name, private [2] $active) {}
}

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Astring

Bint

Cbool

Dfloat

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping the types between the two properties.

Using numeric types for text or boolean values.

The $name is text, so string is correct. The $active is a true/false value, so bool is correct.

5fill in blank

hard

Fill all three blanks to promote properties with correct types and visibility.

PHP

<?php
class Book {
    public function __construct([1] string $title, private [2] $pages, protected [3] $available) {}
}

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Apublic

Bint

Cbool

Dprivate

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong visibility for $title.

Using wrong types for $pages or $available.

The $title property is private, so private is correct. The $pages is a number, so int is correct. The $available is true/false, so bool is correct.