What is null coalescing assignment ??= operator in PHP 7.4

What is null coalescing assignment ??= operator in PHP 7.4

I've just seen a video about upcoming PHP 7.4 features and saw this ??= new operator. I already know the ?? operator. How's this different?


From the docs:

Coalesce equal or ??=operator is an assignment operator. If the left parameter is null, assigns the value of the right paramater to the left one. If the value is not null, nothing is done.

Example:

// The folloving lines are doing the same
$this->request->data['comments']['user_id'] = $this->request->data['comments']['user_id'] ?? 'value';
// Instead of repeating variables with long names, the equal coalesce operator is used
$this->request->data['comments']['user_id'] ??= 'value';

So it's basically just a shorthand to assign a value if it hasn't been assigned before.

PHP 7.4: Null Coalescing Assignment, A brief look at one of the new features arriving in PHP 7.4, the ability to use the null coalescing operator on assignment. The Null Coalesce Assignment Operator is sometimes also called as Null Coalesce Equal Operator. The Null coalesce operator (??) was added so that instead of using isset() along with the ternary operator (?:) we could just use the null coalesce operator (??).


In PHP 7 this was originally released, allowing a developer to simplify an isset() check combined with a ternary operator. For example, before PHP 7, we might have this code:

$data['username'] = (isset($data['username']) ? $data['username'] : 'guest');

When PHP 7 was released, we got the ability to instead write this as:

$data['username'] = $data['username'] ?? 'guest';

Now, however, when PHP 7.4 gets released, this can be simplified even further into:

$data['username'] ??= 'guest';

One case where this doesn't work is if you're looking to assign a value to a different variable, so you'd be unable to use this new option. As such, while this is welcomed there might be a few limited use cases.

What is null coalescing assignment ??= operator in PHP 7.4, 'value'; So it's basically just a shorthand to assign a value if it hasn't been assigned before. In PHP 7 this was originally released, allowing a developer to simplify an isset() check combined with a ternary operator. The new null coalescing assignment operator syntax allows us to succinctly make assignments to null variables. you can see that our new PHP 7.4 assignment is a bit shorter, but you'll also


The null coalescing assignment operator is a shorthand way of assigning the result of the null coalescing operator.

An example from the official release notes:

$array['key'] ??= computeDefault();
// is roughly equivalent to
if (!isset($array['key'])) {
    $array['key'] = computeDefault();
}

PHP 7.4 - Null Coalesce Assignment Operator, The Null Coalesce Assignment Operator (??=) assigns the value of the right- hand parameter if the left-hand parameter is null. It is also called� PHP 7.4 introduced a new Zero Coalesce Assignment Operator?? (=). This is used in combination with isset() method to replace the ternary operation. This operator is used for assigning its right-hand operand value to its left-hand operand only if the left-hand operand value is null.


Example Docs:

$array['key'] ??= computeDefault();
// is roughly equivalent to
if (!isset($array['key'])) {
    $array['key'] = computeDefault();
}

PHP RFC: Null Coalescing Assignment Operator, In PHP 7.0, we got new null coalescing operator (??) which is a syntactic sugar of using isset() for check a value for null. PHP 7.4 has brought new syntactic� No Comments on PHP 7.4 – Null coalescing assignment operator The null coalescing assignment operator is a shorthand for null coalescing operations. Let’s take a example code


Null coalescing assignment operator chaining:

$a = null;
$b = null;
$c = 'c';

$a ??= $b ??= $c;

print $b; // c
print $a; // c

Example at 3v4l.org

PHP 7.4 : Null Coalescing Assignment Operator :: Ataur.net, Improved type variance; The null coalescing assignment operator as a shorthand ; FFI for better extension development in PHP; Underscores can� With PHP 7.4 upcoming, it's time to start exploring some of the new features that will be arriving alongside it. Here we cover the enhancements around the null coalescing operator, namely the introduction of the null coalescing assignment operator. (Sometimes referred to as the "null coalesce equal operator")


What's new in PHP 7.4, PHP 7 - Null Coalescing Operator - In PHP 7, a new feature, null coalescing operator (??) has been introduced. It is used to replace the ternary operation in� PHP 7.4 comes with many good features but this one of my personal favorite. I am sure as a developer, you will also love this short and clean version of code. Basically, this operator helps to remove use of isset() function.


PHP 7 - Null Coalescing Operator, 116 votes, 61 comments. 124k members in the PHP community. Share and discover the latest news about the PHP ecosystem and its community. Please … PHP RFC: Null Coalescing Assignment Operator. Status: Implemented (in PHP 7.4) It is also intuitive to use combined assignment operator null coalesce checking


Null coalescing assignment operator ??= is now confirmed for PHP 7.4, The null coalescing assignment operator (??=) is a fancy term for something that is quite simple to understand. It provides a shorthand for� In PHP 7, a new feature, null coalescing operator (??) has been introduced. It is used to replace the ternary operation in conjunction with isset() function. The Null coalescing operator returns its first operand if it exists and is not NULL; otherwise it returns its second operand. Example