Anonymous function syntax in PHP - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create an anonymous function assigned to $greet.

PHP

$greet = [1]() { echo "Hello!"; };

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

Afun

Bdef

Clambda

Dfunction

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'def' or 'lambda' which are not PHP keywords.

Forgetting the 'function' keyword.

The keyword function is used in PHP to declare an anonymous function.

2fill in blank

medium

Complete the code to call the anonymous function stored in $greet.

PHP

$greet[1]();

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

A->

B()

C[]

D->call

Attempts:

3 left

💡 Hint

Common Mistakes

Using '->' which is for object properties.

Using '[]' which is for arrays.

To call a function stored in a variable in PHP, use parentheses () after the variable.

3fill in blank

hard

Fix the error in the anonymous function syntax.

PHP

$sum = function($a, $b) [1] return $a + $b; };

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

A{

B(

C;

D[

Attempts:

3 left

💡 Hint

Common Mistakes

Using parentheses or brackets instead of curly braces.

Missing the opening brace causes syntax errors.

The function body must start with a curly brace { in PHP anonymous functions.

4fill in blank

hard

Fill the blank to create an anonymous function that uses a variable from outside its scope.

PHP

$multiplier = 3;
$multiply = function($number) use [1] { return $number * $multiplier; };

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

A{$multiplier}

B[$multiplier]

C($multiplier)

D<$multiplier>

Attempts:

3 left

💡 Hint

Common Mistakes

Using square brackets or curly braces after 'use' instead of parentheses.

Forgetting the opening curly brace for the function body.

The use keyword is followed by parentheses enclosing variables to import into the anonymous function's scope, then the function body starts with a curly brace.

5fill in blank

hard

Fill the two blanks to create and call an anonymous function that returns the square of a number.

PHP

$square = function($n) [1] return $n * $n; [2]
echo $square(5);

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

A()

B{

C}

D[]

Attempts:

3 left

💡 Hint

Common Mistakes

Using square brackets instead of parentheses for parameters.

Missing opening or closing curly braces.

The anonymous function syntax requires parentheses for parameters, curly braces to start and end the function body.