php null coalescing assignment operator

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PHP Null Coalescing Operator

Summary : in this tutorial, you’ll learn about the PHP Null coalescing operator to assign a value to a variable if the variable doesn’t exist or null.

Introduction to the PHP null coalescing operator

When working with forms , you often need to check if a variable exists in the $_GET or $_POST by using the ternary operator in conjunction with the isset() construct. For example:

This example assigns the $_POST['name'] to the $name variable if $_POST['name'] exists and not null. Otherwise, it assigns the '' to the $name variable.

To make it more convenient, PHP 7.0 added support for a null coalescing operator that is syntactic sugar of a ternary operator and isset() :

In this example, the ?? is the null coalescing operator. It accepts two operands. If the first operand is null or doesn’t exist, the null coalescing operator returns the second operand. Otherwise, it returns the first one.

In the above example, if the variable name doesn’t exist in the $_POST array or it is null, the ?? operator will assign the string 'John' to the $name variable. See the following example:

As you can see clearly from the output, the ?? operator is like a gate that doesn’t allow null to pass through.

Stacking the PHP Null coalescing operators

PHP allows you to stack the null coalescing operators. For example:

In this example, since the $fullname , $first , and $last doesn’t exist, the $name will take the 'John' value.

PHP null coalescing assignment operator

The following example uses the null coalesing operator to assign the 0 to $counter if it is null or doesn’t exist:

The above statement repeats the variable $counter twice. To make it more concise, PHP 7.4 introduced the null coalescing assignment operator ( ??= ):

In this example, the ??= is the null coalescing assignment operator. It assigns the right operand to the left if the left operand is null. Otherwise, the coalescing assignment operator will do nothing.

It’s equivalent to the following:

In practice, you’ll use the null coalescing assignment operator to assign a default value to a variable if it is null.

• The null coalescing operator ( ?? ) is a syntactic sugar of the ternary operator and isset() .
• The null coalescing assignment operator assigns the right operand to the left one if the left operand is null.

Null Coalescing Operator in PHP: Embracing Graceful Defaults

Introduction.

The null coalescing operator introduced in PHP 7 provides a clean and succinct way to use a default value when a variable is null.

Getting Started with ‘??’

In PHP, the null coalescing operator (??) is a syntactic sugar construct that simplifies the task of checking for the existence and value of a variable. Prior to its introduction in PHP 7, developers would often utilize the isset() function combined with a ternary conditional to achieve a similar result. Let’s see this with a basic code example:

With the null coalescing operator, this simplifies to:

This approach immediately streamlines the code, making it more readable and easier to maintain.

Advancing with Null Coalescing

The operator is not only limited to simple variable checks but can be used with multiple operands, evaluating from left to right until it finds a non-null value. Let’s dive deeper with an advanced example:

This progresses through the $_GET, $_SESSION arrays, and ends with a literal if all else fails.

It also works seamlessly with functions and method calls. For instance:

In this scenario, if getUserFromDatabase($id) returns null, ‘fallback’ will be used.

Working with Complex Structures

The null coalescing operator is versatile, and can be directly applied to multi-dimensional arrays and even JSON objects. Consider the following example:

Let’s take it a step further with objects:

This code elegantly attempts to retrieve a profile picture, defaulting if nothing is returned.

Combining with Other PHP 7 Features

PHP 7 introduces other syntactic improvements such as the spaceship operator (<=>) for comparisons. Combine these with the null coalescing operator for powerful expressions. For example:

Real-World Scenarios

In real-world applications, embracing the null coalescing operator means focusing on the business logic rather than boilerplate checks. It particularly shines in scenarios involving configuration, forms, APIs, and conditional displays. The operator often becomes indispensable in modern PHP development workflows.

For instance, when processing API input:

Or, setting up a GUI with language fallbacks:

Good Practices and Pitfalls

While highly practical, there are scenarios where the null coalescing operator isn’t suitable. It should not replace proper validation and sanitization of user data, nor should it be overused in complex conditions where clearer logic may be needed for maintenance purposes. As with any tool in programming, using it judiciously is key.

Performance Implications

Performance-wise, the null coalescing operator is a favorable choice. Typically, it’s faster than combining isset() with a ternary operator due to reduced opcode generation. Let’s validate with a timed test:

You’re likely to notice slight but consistent speed advantages using the null coalescing operator.

The null coalescing operator in PHP streamlines default value assignment and contributes to cleaner code. As PHP continues to evolve, adopting such features not only leverages language efficiency but also enhances developer expressiveness and intent. In essence, the ?? operator fine-tunes the syntax dance that we perform every day as PHP developers.

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PHP's double question mark, or the null coalescing operator

The null coalescing operator (??), or the double question mark

The null coalescing operator , or double question mark, was introduced in PHP 7.0 and is a handy shortcut that helps you write cleaner and more readable code. It’s represented by two question marks ?? .

Let’s say you want to get a value from a variable, but if that variable is not set or is null , you want to use a default value instead. You can use the ?? operator to do this in one step.

For example:

This line of code will set $name to $_GET['name'] if it’s set and not null. Otherwise, it will set $name to “Unknown”.

You can also chain them together like this:

This will check $foo first, then $bar , and use “baz” if neither are set and not null.

The null coalescing assignment operator (??=), or the double question mark equals

PHP 7.4 introduced a new shortcut, ??= (double question mark equals), also called the null coalescing assignment operator . This is used when you want to set a variable to a new value only if it’s currently not set or null.

It’s hard to make up a good example, but here’s a simplified one from this very blog’s codebase:

This will set $now to a new DateTime instance only if it’s not already set (or null in that case).

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The PHP null coalescing operator (??) explained

The operator returns the first operand when the value is not null. Otherwise, it returns the second operand.

Stacking the null coalescing operands in PHP

Null coalescing assignment operator in php.

And that’s how you assign a variable value using the null coalescing operator.

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• Web Development

What Is the Null Coalescing Assignment Operator in PHP?

• Daniyal Hamid
• 29 Nov, 2021

Starting with PHP 7.4+, you can use the null coalescing assignment operator ( ??= ). It is a shorthand to assign a value to a variable if it hasn't been set already. Consider the following examples, which are all equivalent:

The null coalescing assignment operator only assigns the value if $x is null or not set. For example:

This post was published 29 Nov, 2021 by Daniyal Hamid . Daniyal currently works as the Head of Engineering in Germany and has 20+ years of experience in software engineering, design and marketing. Please show your love and support by sharing this post .

PHP RFC: Null Coalescing Assignment Operator

• Version: 0.1.0
• Date: 2016-03-09
• Author: Midori Kocak, [email protected]
• Status: Implemented (in PHP 7.4)
• First Published at: http://wiki.php.net/rfc/null_coalesce_equal_operator
• Introduction

Combined assignment operators have been around since 1970's, appearing first in the C Programming Language. For example, $x = $x + 3 can be shortened to $x += 3 . With PHP being a web focused language, the ?? operator is often used to check something's existence like $username = $_GET['user'] ?? 'nobody'; However, because variable names are often much longer than $username, the use of ?? for self assignment creates repeated code, like $this->request->data['comments']['user_id'] = $this->request->data['comments']['user_id'] ?? ‘value’; . It is also intuitive to use combined assignment operator null coalesce checking for self assignment.

Despite ?? coalescing operator being a comparison operator, 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 made.

The value of right-hand parameter is copied if the left-hand parameter is null.

• Proposed PHP Version(s)

This proposed for the next PHP 7.x.

• Patches and Tests

A pull request with a working implementation, targeting master, is here: https://github.com/php/php-src/pull/1795

As this is a language change, a 2/3 majority is required. A straight Yes/No vote is being held.

Voting started at 2016/03/24 16:08 and will be closed at 2016/04/02.

Links to external references, discussions or RFCs

http://programmers.stackexchange.com/questions/134118/why-are-shortcuts-like-x-y-considered-good-practice

• Rejected Features

Keep this updated with features that were discussed on the mail lists.

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Table of Contents

PHP 7.4: Null Coalescing Assignment

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”)

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:

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

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

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.

So for example, this code from before PHP 7 could only be optimised once using the null coalescing operator, and not the assignment operator:

01 Jan 2020

• development

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 sugar to assign default value to a variable if it is null.

Lets say, we have a variable called $student_name which should contain student name in it. But for some reason, sometimes student name may can't be found (null value), so we need to assign default value to it before using it. In PHP <7.4 , we would do something like this:

In line 5, we are checking if $student_name has been set, if not we are assigning 'Default Name' to it.

In PHP 7.4, we can use Null Coalescing Assignment Operator (??=) to do the same:

Above, Null Coalescing Assignment Operator checks if $student_name is null, if so it assign string(12) "Default Name" to it.

Best benefit of Null Coalescing Assignment Operator is when used for array element. lets say, we have an variable for a blog post which is array

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• Best Practices ,

PHP null coalescing operator

Hello everyone, I'm relatively new to PHP and I recently came across the term "null coalescing operator." I have heard people mention it, but I'm not entirely sure what it does and how it can be used in my code. To give you some context, I am working on a project where I need to handle situations where variables might be null. I've been using conditionals and ternary operators to check for null values, but I've heard that the null coalescing operator could simplify my code. So my question is, what exactly is the null coalescing operator in PHP? How does it work and what are some practical use cases for it? I would appreciate it if someone could explain it to me in a way that is beginner-friendly and provide some code examples to illustrate its usage. Thank you in advance for your help!

All Replies

Hey there! I've been using the null coalescing operator in my PHP projects for a while now, and I must say, it's a fantastic addition to the language. As the name suggests, it helps in tackling situations where you need to handle null values. Here's how it works: the null coalescing operator (`??`) allows you to assign a default value to a variable if it is null. It's a concise way to check if a variable is null and provide an alternative value in a single expression. For example, let's say you have a variable `$name` that might be null. Instead of using an if statement or ternary operator, you can use the null coalescing operator like this: $defaultName = "Guest"; $fullName = $name ?? $defaultName; In this case, if `$name` is not null, the value of `$name` will be assigned to `$fullName`. However, if `$name` is null, `$defaultName` will be assigned to `$fullName`. It's a neat shortcut that keeps your code clean and concise. Another use case is when working with arrays. Suppose you have an associative array `$data` that may or may not have a key called `'email'`. To assign a default email if the `'email'` key is missing or null, you can use the null coalescing operator like this: $defaultEmail = "[email protected]"; $email = $data['email'] ?? $defaultEmail; If `$data['email']` exists and is not null, `$email` will be assigned its value. Otherwise, the default email address will be assigned. I've found the null coalescing operator to be handy in scenarios where you want to provide fallback values without writing lengthy if-else blocks or ternary statements. It definitely simplifies the code and makes it more readable. I hope this helps you understand and use the null coalescing operator effectively in your PHP projects. Feel free to ask if you have any more questions!

Hey everyone, I just wanted to chime in and share my experience with the null coalescing operator in PHP. I've been using it extensively in my projects, and it has proven to be a real time-saver. One particular use case where the null coalescing operator shines is when dealing with form input data. Typically, you would handle form submissions by checking if each field has a value or is null before using it. With the null coalescing operator, you can simplify this process and handle default values elegantly. Let's say you have a form with various inputs, such as name, email, and phone number. To avoid errors when these fields are left blank, you can utilize the null coalescing operator to assign default values. php $name = $_POST['name'] ?? "Anonymous"; $email = $_POST['email'] ?? "[email protected]"; $phone = $_POST['phone'] ?? "N/A"; In this example, if the corresponding `$_POST` variable is not null, the value will be assigned to the respective variable. However, if the field is null (left blank in the form), the null coalescing operator will assign the provided default value instead. This approach saves you from writing verbose conditional statements to handle each form input individually. It condenses the code and makes it more readable. Not only does the null coalescing operator simplify handling null values, but it also allows for cleaner code in cases where API responses or database query results may contain null values. Instead of manually checking each value, you can leverage the operator and set appropriate defaults or fallback values as needed. Overall, the null coalescing operator in PHP is a powerful tool for gracefully handling null values and reducing code complexity. I highly recommend integrating it into your PHP projects for smoother data handling. If you have any questions or need further clarification, feel free to ask. Happy coding!

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Hello all, I couldn't resist joining the discussion on the null coalescing operator in PHP. As a seasoned PHP developer, I can't stress enough how much it has improved my code readability and reduced boilerplate code. One practical use case I'd like to share is dealing with database results. We often fetch data from a database and assign it to variables, but sometimes certain fields may be null. That's where the null coalescing operator comes in handy. Imagine a scenario where you're fetching user records and want to display their names. Some users may not have specified their first name, so the database field would be null. Instead of writing lengthy if-else statements, the null coalescing operator provides an elegant solution. php $firstName = $user['first_name'] ?? "Unknown"; $lastName = $user['last_name'] ?? "Unknown"; With just a single line for each variable, we're able to handle null values effortlessly. If `first_name` or `last_name` is null, the corresponding variable will be assigned the default value of "Unknown". This not only streamlines the code but also improves legibility. It becomes much easier to track the intention of assigning default values to variables without bloating the codebase. Additionally, the null coalescing operator is a blessing when working with APIs. Sometimes APIs may have optional fields that could be null if not provided. By employing the null coalescing operator, you can quickly set fallback values to ensure your code continues to function seamlessly. To sum it up, the null coalescing operator is an essential tool that simplifies handling null values in PHP. Whether it's handling user input, database records, or API responses, this operator proves to be an elegant and efficient solution. If you have any questions or need further insights, feel free to ask. Happy coding, everyone!

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Null Coalescing Operator

The null coalescing operator ( ?? ) in PHP is a shorthand way of checking if a value is "null", meaning it's either NULL or undefined , and if it is, providing a default value in its place. It can be used as a cleaner and more concise alternative to the ternary operator or conditional statement.

The result of $a ?? $b is:

• if $a is defined, then $a ,
• if $a isn't defined, then $b .

Using the null coalescing operator

The basic syntax of the null coalescing operator is as follows:

In this example, $someVariable is checked for a value. If it has a value that is not "null", it is assigned to $data . If $someVariable is "null", the default value "Default value" is assigned to $data .

The most common use case for this operator is to set a default value for a variable. For example:

If the $user variable has a value, we can assume the user is logged in. Otherwise, we'll refer to the user as "Anonymous" .

Create a variable called $email . Its value should be $userEmail or a default value of false . Use the null coalescing operator.

Key takeaways

• The null coalescing operator is written with the ?? characters.
• PHP checks for a value on the left. If the value is not null or undefined , the value on the left will be returned.
• Otherwise, the value on the right of the operator is returned.

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The Null Coalescing operator is one of the many new features introduced in PHP 7. The word "coalescing" means uniting many things into one. This operator is used to replace the ternary operation in conjunction with the isset() function.

Ternary Operator in PHP

PHP has a ternary operator represented by the " ? " symbol. The ternary operator compares a Boolean expression and executes the first operand if it is true, otherwise it executes the second operand.

Let us use the ternary operator to check if a certain variable is set or not with the help of the isset() function, which returns true if declared and false if not.

It will produce the following output −

Now, let's remove the declaration of "x" and rerun the code −

The code will now produce the following output −

The Null Coalescing Operator

The Null Coalescing Operator is represented by the "??" symbol. It acts as a convenient shortcut to use a ternary in conjunction with isset(). It returns its first operand if it exists and is not null; otherwise it returns its second operand.

The first operand checks whether a certain variable is null or not (or is set or not). If it is not null, the first operand is returned, else the second operand is returned.

Take a look at the following example −

Now uncomment the first statement that sets $num to 10 and rerun the code −

It will now produce the following output −

A useful application of Null Coalescing operator is while checking whether a username has been provided by the client browser.

The following code reads the name variable from the URL. If indeed there is a value for the name parameter in the URL, a Welcome message for him is displayed. However, if not, the user is called Guest.

Assuming that this script "hello.php" is in the htdocs folder of the PHP server, enter http://localhost/hello.php?name=Amar in the URL, the browser will show the following message −

If http://localhost/hello.php is the URL, the browser will show the following message −

The Null coalescing operator is used as a replacement for the ternary operator’s specific case of checking isset() function. Hence, the following statements give similar results −

You can chain the "??" operators as shown below −

This will set the username to Guest if the variable $name is not set either by GET or by POST method.

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PHP Operators Null Coalescing Operator (??)

Fastest entity framework extensions.

Null coalescing is a new operator introduced in PHP 7. This operator returns its first operand if it is set and not NULL . Otherwise it will return its second operand.

The following example:

is equivalent to both:

This operator can also be chained (with right-associative semantics):

which is an equivalent to:

Note: When using coalescing operator on string concatenation dont forget to use parentheses ()

This will output John only, and if its $firstName is null and $lastName is Doe it will output Unknown Doe . In order to output John Doe , we must use parentheses like this.

This will output John Doe instead of John only.

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• Migrating from PHP 5.6.x to PHP 7.0.x

New features

Scalar type declarations.

Scalar type declarations come in two flavours: coercive (default) and strict. The following types for parameters can now be enforced (either coercively or strictly): strings ( string ), integers ( int ), floating-point numbers ( float ), and booleans ( bool ). They augment the other types introduced in PHP 5: class names, interfaces, array and callable .

The above example will output:

To enable strict mode, a single declare directive must be placed at the top of the file. This means that the strictness of typing for scalars is configured on a per-file basis. This directive not only affects the type declarations of parameters, but also a function's return type (see return type declarations , built-in PHP functions, and functions from loaded extensions.

Full documentation and examples of scalar type declarations can be found in the type declaration reference.

Return type declarations

PHP 7 adds support for return type declarations . Similarly to argument type declarations , return type declarations specify the type of the value that will be returned from a function. The same types are available for return type declarations as are available for argument type declarations.

Full documentation and examples of return type declarations can be found in the return type declarations . reference.

Null coalescing operator

The null coalescing operator ( ?? ) has been added as syntactic sugar for the common case of needing to use a ternary in conjunction with isset() . It returns its first operand if it exists and is not null ; otherwise it returns its second operand.

Spaceship operator

The spaceship operator is used for comparing two expressions. It returns -1, 0 or 1 when $a is respectively less than, equal to, or greater than $b . Comparisons are performed according to PHP's usual type comparison rules .

Constant arrays using define()

Array constants can now be defined with define() . In PHP 5.6, they could only be defined with const .

Anonymous classes

Support for anonymous classes has been added via new class . These can be used in place of full class definitions for throwaway objects:

Full documentation can be found in the anonymous class reference .

Unicode codepoint escape syntax

This takes a Unicode codepoint in hexadecimal form, and outputs that codepoint in UTF-8 to a double-quoted string or a heredoc. Any valid codepoint is accepted, with leading 0's being optional.

Closure::call()

Closure::call() is a more performant, shorthand way of temporarily binding an object scope to a closure and invoking it.

Filtered unserialize()

This feature seeks to provide better security when unserializing objects on untrusted data. It prevents possible code injections by enabling the developer to whitelist classes that can be unserialized.

The new IntlChar class seeks to expose additional ICU functionality. The class itself defines a number of static methods and constants that can be used to manipulate unicode characters.

In order to use this class, the Intl extension must be installed.

Expectations

Expectations are a backwards compatible enhancement to the older assert() function. They allow for zero-cost assertions in production code, and provide the ability to throw custom exceptions when the assertion fails.

While the old API continues to be maintained for compatibility, assert() is now a language construct, allowing the first parameter to be an expression rather than just a string to be evaluated or a bool value to be tested.

Full details on this feature, including how to configure it in both development and production environments, can be found on the manual page of the assert() language construct.

Group use declarations

Classes, functions and constants being imported from the same namespace can now be grouped together in a single use statement.

Generator Return Expressions

This feature builds upon the generator functionality introduced into PHP 5.5. It enables for a return statement to be used within a generator to enable for a final expression to be returned (return by reference is not allowed). This value can be fetched using the new Generator::getReturn() method, which may only be used once the generator has finished yielding values.

Being able to explicitly return a final value from a generator is a handy ability to have. This is because it enables for a final value to be returned by a generator (from perhaps some form of coroutine computation) that can be specifically handled by the client code executing the generator. This is far simpler than forcing the client code to firstly check whether the final value has been yielded, and then if so, to handle that value specifically.

Generator delegation

Generators can now delegate to another generator, Traversable object or array automatically, without needing to write boilerplate in the outermost generator by using the yield from construct.

Integer division with intdiv()

The new intdiv() function performs an integer division of its operands and returns it.

Session options

session_start() now accepts an array of options that override the session configuration directives normally set in php.ini.

These options have also been expanded to support session.lazy_write , which is on by default and causes PHP to only overwrite any session file if the session data has changed, and read_and_close , which is an option that can only be passed to session_start() to indicate that the session data should be read and then the session should immediately be closed unchanged.

For example, to set session.cache_limiter to private and immediately close the session after reading it:

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Now, callbacks can be registered to each regular expression using an associative array, where the key is a regular expression and the value is a callback.

CSPRNG Functions

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list() can always unpack objects implementing ArrayAccess

Previously, list() was not guaranteed to operate correctly with objects implementing ArrayAccess . This has been fixed.

Other Features

• Class member access on cloning has been added, e.g. (clone $foo)->bar() .

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Nullish coalescing operator

널 병합 연산자 ( ?? ) 는 왼쪽 피연산자가 null 또는 undefined 일 때 오른쪽 피연산자를 반환하고, 그렇지 않으면 왼쪽 피연산자를 반환하는 논리 연산자이다.

이는 왼쪽 피연산자가 null 또는 undefined 뿐만 아니라 falsy 값에 해당할 경우 오른쪽 피연산자를 반환하는 논리 연산자 OR ( || ) 와는 대조된다. 다시 말해 만약 어떤 변수 foo에게 falsy 값( '' 또는 0 )을 포함한 값을 제공하기 위해 || 을 사용하는 것을 고려했다면 예기치 않는 동작이 발생할 수 있다. 하단에 더 많은 예제가 있다.

널 병합 연산자는 연산자 우선 순위 가 다섯번째로 낮은데, || 의 바로 아래이며 조건부 (삼항) 연산자 의 바로 위이다.

널 병합 연산자는 만약 왼쪽 표현식이 null 또는 undefined 인 경우, 오른쪽 표현식의 결과를 반환한다.

이전에는 변수에 기본값을 할당하고 싶을 때, 논리 연산자 OR ( || )을 사용하는 것이 일반적인 패턴이다:

그러나 || boolean 논리 연산자 때문에, 왼쪽 피연산자는 boolean으로 강제로 변환되었고 falsy 한 값( 0 , '' , NaN , null , undefined )은 반환되지 않았다. 이 동작은 만약 0 , '' or NaN 을 유효한 값으로 생각한 경우 예기치 않는 결과를 초래할 수 있다.

널 병합 연산자는 첫 번째 연산자가 null 또는 undefined 로 평가될 때만, 두 번째 피연산자를 반환함으로써 이러한 위험을 피한다:

OR과 AND 같은 논리 연산자들과 마찬가지로, 만약 왼쪽이 null 또는 undefined 가 아님이 판명되면 오른쪽 표현식은 평가되지 않는다.

No chaining with AND or OR operators

AND ( && ) 와 OR 연산자 ( || )를 ?? 와 직접적으로 결합하여 사용하는 것은 불가능하다. 이 경우 SyntaxError 가 발생된다.

그러나 우선 순위를 명시적으로 나타내기 위해 괄호를 사용하면 가능하다:

Optional chaining 연산자( ?. )와의 관계

널 병합 연산자는 명확한 값으로 undefined 과 null 을 처리하고, optional chaining 연산자 ( ?. ) 는 null or undefined 일 수 있는 객체의 속성에 접근할 때 유용하다.

이 예제는 기본 값을 제공하지만 null or undefined 이외의 값을 를 유지한다.

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• The optional chaining operator
• The logical OR ( || ) operator
• Default paramaters in functions

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Null Coalescing Assignment Operator throwing parse / syntax error in PHP 8.0

I'm transitioning from 7.3 to PHP 8.0 (centOS) and going through the fun process of patching hordes of undefined array keys. It's easy, but time consuming. One new tool offered by PHP I hoped would offset this burden is the new Null Coalescing Assignment Operator ??= added in 7.4

https://www.php.net/manual/en/migration74.new-features.php#migration74.new-features.core.null-coalescing-assignment-operator

However, any use of this operator is throwing a parse error:

Example Code (based on PHP example linked above):

Anyone run into this / know what I'm missing?

• syntax-error
• null-coalescing-operator
• php-parse-error

• 2 Just to make sure, you're doing this on your 8.0 system, and not your 7.3 system, right? –  Tim Roberts May 28, 2022 at 3:36
• Tested but no errors on PHP 7.4+ –  vee May 28, 2022 at 3:44
• @TimRoberts yeah, I triple checked. First thing I thought as well. The domain I'm working in is set as 8.0 in WHM / CentOS v7.7. Going to ping this off a host admin and see if they can dig anything up. Will self-answer if I figure it out. Thanks –  jtubre May 28, 2022 at 18:25
• 1 Use phpversion() , or PHP_VERSION in the code you are running to see what exactly version it is. Do not look at version number from anywhere else because it can be different. –  vee May 28, 2022 at 18:39

Got it. Edge-case, but in case anyone else runs into this issue on a multiPHP server, I realized the error was only being thrown when the script was cronned. The cron job command was pointing to the general PHP binary /usr/local/bin/php .

Pointing to the specific PHP8 binary /opt/cpanel/ea-php80/root/bin/php in the command did the trick.

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