assignment operators in php 7

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Php advanced, mysql database, php examples, php reference, php operators.

Operators are used to perform operations on variables and values.

PHP divides the operators in the following groups:

• Arithmetic operators
• Assignment operators
• Comparison operators
• Increment/Decrement operators
• Logical operators
• String operators
• Array operators
• Conditional assignment operators

PHP Arithmetic Operators

The PHP arithmetic operators are used with numeric values to perform common arithmetical operations, such as addition, subtraction, multiplication etc.

PHP Assignment Operators

The PHP assignment operators are used with numeric values to write a value to a variable.

The basic assignment operator in PHP is "=". It means that the left operand gets set to the value of the assignment expression on the right.

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PHP Comparison Operators

The PHP comparison operators are used to compare two values (number or string):

PHP Increment / Decrement Operators

The PHP increment operators are used to increment a variable's value.

The PHP decrement operators are used to decrement a variable's value.

PHP Logical Operators

The PHP logical operators are used to combine conditional statements.

PHP String Operators

PHP has two operators that are specially designed for strings.

PHP Array Operators

The PHP array operators are used to compare arrays.

PHP Conditional Assignment Operators

The PHP conditional assignment operators are used to set a value depending on conditions:

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PHP Assignment Operators

Php tutorial index.

PHP assignment operators applied to assign the result of an expression to a variable. = is a fundamental assignment operator in PHP. It means that the left operand gets set to the value of the assignment expression on the right.

PHP 7 Operators with Example

This tutorial will describe PHP 7 operators with example . The Operators help to perform operations on variables and values.

There are some new operators introduced into php 7, like the null coalescing operator ( ?? ), spaceship operator( <=> ).

Here, We will discuss all php7 operators with examples. We will go through one by one operator types in PHP 7. There are the following operator groups available in PHP 7.

PHP Arithmetic Operators

PHP 7 Arithmetic Operators Example

Php 7 assignment operators.

This type php 7 operator are used to assign values to variables.The left operands gets set to the value of the assignment expression on the right.

PHP 7 Assignment Operators Example

Php comparison operators.

The PHP 7 Comparison Operators help to compare two variables. You can also compare two different types of variables as well.

PHP 7 comparison Operators Example

Php 7 increment / decrement operators.

The PHP 7 increment operators are used to increment a variable’s value whereas Decrement Operators used to decrement a variable’s value.

PHP 7 Incrementing and Decrementing Operators Example

Php 7 logical operators.

The PHP 7 logical operators are used to combine two conditions. You can combine two variable conditions using logical operators.

PHP 7 Logical Operators Example

Php 7 string operators.

There are the following operators for string manipulation.Its specially designed for string types variables.

PHP 7 String Operators Example

Php 7 array operators.

PHP 7 also provides operators for array type variables, you can compare two arrays using the following array operators.

PHP 7 Conditional Assignment Operators

PHP 7 Conditional Assignment Operators Example

Php 7 spaceship operator.

These operators are introduced into PHP 7. The operand (<=>) is used for comparing two expressions. This is a three-way comparison operator and it can perform greater than, less than, and equal comparisons between two operands.

The spaceship operator returns 0 if both operands are equal, 1 if the left is greater, and -1 if the right is greater.

PHP 7 Spaceship Operator Example

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PHP Assignment Operators

In this tutorial, you shall learn about Assignment Operators in PHP, different Assignment Operators available in PHP, their symbols, and how to use them in PHP programs, with examples.

Assignment Operators

Assignment Operators are used to perform to assign a value or modified value to a variable.

Assignment Operators Table

The following table lists out all the assignment operators in PHP programming.

In the following program, we will take values in variables $x and $y , and perform assignment operations on these values using PHP Assignment Operators.

PHP Program

Assignment Operators Tutorials

The following tutorials cover each of the Assignment Operators in PHP in detail with examples.

• PHP Simple Assignment
• PHP Addition Assignment
• PHP Subtraction Assignment
• PHP Multiplication Assignment
• PHP Division Assignment
• PHP Modulus Assignment

In this PHP Tutorial , we learned about all the Assignment Operators in PHP programming, with examples.

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• Assignment Operators

PHP assignment operators enable you to frequently engage in performing calculations and operations on variables, requiring the assignment of results to other variables. Consequently, this is precisely where assignment operators prove indispensable, allowing you to seamlessly execute an operation and assign the result to a variable within a single statement.

In the following sections, we’ll delve into the different types of PHP assignment operators and explore how to use them.

Table of Contents

Php arithmetic assignment operators, php bitwise assignment operators.

• Null Coalescing Operator

Assigning a Reference to a PHP Variable

Other assignment operators, wrapping up.

The most commonly used assignment operator in PHP is the equals sign (=). For instance, in the following code, the value 10 is assigned to the variable $x:

Now, let’s explore each type with examples:

Numeric data undergoes mathematical operations through the utilization of arithmetic operators. In PHP, this is where arithmetic assignment operators come into play, employed to perform these operations. The arithmetic assignment operators include:

• += or $x + $y (Addition Assignment Operator)
• -= or $x - $y (Subtraction Assignment Operator)
• *= or $x * $y (Multiplication Assignment Operator)
• /= or $x / $y (Division Assignment Operator)
• %= or $x % $y (Modulus Assignment Operator)
• **= or $x ** $y (Exponentiation Assignment Operator)

Consider the following example:

In this example, the addition assignment operator increases the value of $x by 5, and then assigns the result back to $x, producing an output of 15.

You can leverage these arithmetic assignment operators to perform complex calculations in a single statement, making your code more concise and easier to read. For more details, refer to this tutorial .

One crucial aspect of computer science involves the manipulation of binary bits in PHP. Let’s delve into one of the more complex assignment operators—specifically, the PHP bitwise operators.

Developers use bitwise operators to manipulate data at the bit level. PHP bitwise assignment operators perform bitwise operations. Here are the bitwise assignment operators:

• &= or $x & $y (Bitwise AND Assignment Operator)
• |= or $x | $y (Bitwise OR Assignment Operator)
• ^= or $x ^ $y (Bitwise XOR Assignment Operator)
• ~= or $x ~ $y (Bitwise NOT Assignment Operator)
• <<= or $x << $y (Left Shift Assignment Operator)
• >>= or $x >> $y (Right Shift Assignment Operator)

Let’s illustrate with an example:

In this example, a bitwise OR operation is performed between the values of $x and 2 using the bitwise OR assignment operator. The result is then assigned to $x, yielding an output of 7.

Here is a full explanation along with more examples of bitwise operators .

Let’s move to the section below to understand the Null Coalescing Operator in PHP.

Furthermore, developers use the null coalescing operator to assign a default value to a variable if it is null. The double question mark (??) symbolizes the null coalescing operator. Consider the following example:

In this example, the null coalescing operator is used to assign the value ‘John Doe’ to the variable $fullName. If $name is null, the value ‘John Doe’ will be assigned to $fullName.

The null coalescing operator simplifies code by enabling the assignment of default values to variables. By reading this tutorial , you will gain more information about it

Anyway, assigning a reference in PHP is one of the language’s benefits, enabling developers to set a value and refer back to it anywhere during the script-writing process. Let’s move to the section below to take a closer look at this concept.

Furthermore, individuals use the reference assignment operator =& to assign a reference to a variable rather than copying the value of the variable. Consider the following example:

In this example, a reference to the variable $x is created using the reference assignment operator. The value 10 is then assigned to $x, and the output displays the value of $y. Since $y is a reference to $x, it also changes to 10, resulting in an output of 10.

The reference assignment operator proves useful when working with large data sets, enabling you to avoid copying large amounts of data.

Let’s explore some other assignment operators in the paragraphs below.

In addition to the arithmetic, bitwise, null coalescing, and reference assignment operators, PHP provides other assignment operators for specific use cases. These operators are:

• .= (Concatenation Assignment Operator)
• ??= (Null Coalescing Assignment Operator)

Now, let’s explore each of these operators in turn:

Concatenation Assignment Operator: Used to concatenate a string onto the end of another string. For example:

In this example, the concatenation assignment operator appends the value of $string2 to the end of $string1, resulting in the output “Hello World!”.

The Null Coalescing Assignment Operator is employed to assign a default value to a variable when it is detected as null. For example:

In this example, the null coalescing assignment operator assigns the value ‘John Doe’ to the variable $name. If $name is null, the value ‘John Doe’ will be assigned to $name.

Let’s summarize it.

we’ve taken a comprehensive look at the different types of PHP assignment operators and how to use them. Assignment operators are essential tools for any PHP developer, facilitating calculations and operations on variables while assigning results to other variables in a single statement.

Moreover, leveraging assignment operators allows you to make your code more concise, easier to read, and helps in avoiding common programming errors.

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PHP Operators

In this tutorial you will learn how to manipulate or perform the operations on variables and values using operators in PHP.

What is Operators in PHP

Operators are symbols that tell the PHP processor to perform certain actions. For example, the addition ( + ) symbol is an operator that tells PHP to add two variables or values, while the greater-than ( > ) symbol is an operator that tells PHP to compare two values.

The following lists describe the different operators used in PHP.

PHP Arithmetic Operators

The arithmetic operators are used to perform common arithmetical operations, such as addition, subtraction, multiplication etc. Here's a complete list of PHP's arithmetic operators:

The following example will show you these arithmetic operators in action:

PHP Assignment Operators

The assignment operators are used to assign values to variables.

The following example will show you these assignment operators in action:

PHP Comparison Operators

The comparison operators are used to compare two values in a Boolean fashion.

The following example will show you these comparison operators in action:

PHP Incrementing and Decrementing Operators

The increment/decrement operators are used to increment/decrement a variable's value.

The following example will show you these increment and decrement operators in action:

PHP Logical Operators

The logical operators are typically used to combine conditional statements.

The following example will show you these logical operators in action:

PHP String Operators

There are two operators which are specifically designed for strings .

The following example will show you these string operators in action:

PHP Array Operators

The array operators are used to compare arrays:

The following example will show you these array operators in action:

PHP Spaceship Operator PHP 7

PHP 7 introduces a new spaceship operator ( <=> ) which can be used for comparing two expressions. It is also known as combined comparison operator.

The spaceship operator returns 0 if both operands are equal, 1 if the left is greater, and -1 if the right is greater. It basically provides three-way comparison as shown in the following table:

The following example will show you how spaceship operator actually works:

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PHP Operators

In this article, we will see how to use the operators in PHP, & various available operators along with understanding their implementation through the examples.

Operators are used to performing operations on some values. In other words, we can describe operators as something that takes some values, performs some operation on them, and gives a result. From example, “1 + 2 = 3” in this expression ‘+’ is an operator. It takes two values 1 and 2, performs an addition operation on them to give 3. 

Just like any other programming language, PHP also supports various types of operations like arithmetic operations(addition, subtraction, etc), logical operations(AND, OR etc), Increment/Decrement Operations, etc. Thus, PHP provides us with many operators to perform such operations on various operands or variables, or values. These operators are nothing but symbols needed to perform operations of various types. Given below are the various groups of operators:

• Arithmetic Operators
• Logical or Relational Operators
• Comparison Operators
• Conditional or Ternary Operators
• Assignment Operators
• Spaceship Operators (Introduced in PHP 7)
• Array Operators
• Increment/Decrement Operators
• String Operators

Let us now learn about each of these operators in detail.

Arithmetic Operators: 

The arithmetic operators are used to perform simple mathematical operations like addition, subtraction, multiplication, etc. Below is the list of arithmetic operators along with their syntax and operations in PHP.

Note : The exponentiation has been introduced in PHP 5.6. 

Example : This example explains the arithmetic operator in PHP.

Logical or Relational Operators:

These are basically used to operate with conditional statements and expressions. Conditional statements are based on conditions. Also, a condition can either be met or cannot be met so the result of a conditional statement can either be true or false. Here are the logical operators along with their syntax and operations in PHP.

Example : This example describes the logical & relational operator in PHP.

Comparison Operators: These operators are used to compare two elements and outputs the result in boolean form. Here are the comparison operators along with their syntax and operations in PHP.

Example : This example describes the comparison operator in PHP.

Conditional or Ternary Operators :

These operators are used to compare two values and take either of the results simultaneously, depending on whether the outcome is TRUE or FALSE. These are also used as a shorthand notation for if…else statement that we will read in the article on decision making. 

Here, the condition will either evaluate as true or false. If the condition evaluates to True, then value1 will be assigned to the variable $var otherwise value2 will be assigned to it.

Example : This example describes the Conditional or Ternary operators in PHP.

Assignment Operators: These operators are used to assign values to different variables, with or without mid-operations. Here are the assignment operators along with their syntax and operations, that PHP provides for the operations.

Example : This example describes the assignment operator in PHP.

Array Operators: These operators are used in the case of arrays. Here are the array operators along with their syntax and operations, that PHP provides for the array operation.

Example : This example describes the array operation in PHP.

Increment/Decrement Operators: These are called the unary operators as they work on single operands. These are used to increment or decrement values.

Example : This example describes the Increment/Decrement operators in PHP. 

String Operators: This operator is used for the concatenation of 2 or more strings using the concatenation operator (‘.’). We can also use the concatenating assignment operator (‘.=’) to append the argument on the right side to the argument on the left side.

Example : This example describes the string operator in PHP.

Spaceship Operators :

PHP 7 has introduced a new kind of operator called spaceship operator. The spaceship operator or combined comparison operator is denoted by “<=>“. These operators are used to compare values but instead of returning the boolean results, it returns integer values. If both the operands are equal, it returns 0. If the right operand is greater, it returns -1. If the left operand is greater, it returns 1. The following table shows how it works in detail:

Example : This example illustrates the use of the spaceship operator in PHP.

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Ternary and Ternary Coalescing Operator in PHP

PHP supports various forms of ternary and coalescing operators. This is a quick post to catch-up to all ternary and coalescing operators supports in PHP.

1. Ternary Operator: cond ? expr1 : expr2

Ternary operator is a short form for an if/else block that executes exactly one expression each.

The if/else block above is quite verbose and consumes more space for a simple expression. With the ternary operator, you can optimize this:

Its syntax is follows:

PHP will execute condition condition, and if it evaluates to "true-ish" value (same semantics as an if() condition), value from expression-if-true is used. If condition evaluates to false, value from expression-if-false will be used.

An ideal use case of Ternary operator would be assignments that can have two values.

From PHP 8.0+, you can also throw an exception from a Ternary operator .

2. Shorthand Ternary Operator: cond ?: else-expr

Certain Ternary operator expressions can be simplified further. Consider the following Ternary expression:

If the conditional expression is the same as the true-expression, it is possible to reduce this further:

If load_user() function returns a false-ish value, $user will be assigned false . Otherwise, the return value of load_user() will be assigned.

Its syntax is:

The cond condition will be evaluated as if it's in an if() block, and the return value will be assigned to result if it is a truthy value. If it's a false-ish value (such as 0 , "0" , false , null , [] , etc), the expression-if-false expression will be evaluated, and its return value will be assigned to result .

3. Null Coalescing Operator

Null Coalescing Operator provides a shorthand for isset() calls. It is often used to reduce excessive isset() calls. Null Coalescing operator calls isset() on the conditional expression, and the value will be returned.

If $_GET['value'] is set (which behaves exactly the way isset() does), $_GET['value'] value will be assigned to $result . If it is not set, or null , foo will be assigned to $result .

PHP calls isset(variable) , and variable will be assigned to result if variable is set. If it is not set, expression will be evaluated, and its value will be assigned to result .

4. Null Coalescing Assignment operator

Null Coalescing operator can be be further reduced in PHP 7.4, with Null Coalescing Assignment operator .

A word of caution

Be mindful when you chain ternary/coalescing operators. It is now required to use braces to make the intent clear if you absolutely have to use ternary/coalescing operators.

Null Coalescing Assignment operator is relatively new in PHP (added in PHP 7.4), so you code might not work in older PHP versions if you decide to use that operator.

These operators are syntax sugar only, and do not provide any meaningful performance difference compared to good ol' if/else blocks. When the intent is not clear, it is recommended to go with if/else blocks although they make the code slightly verbose

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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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PHP Advance

Operators - php basics.

Operators are symbols that instruct the PHP processor to carry out specific actions. For example, the addition ( + ) symbol instructs PHP to add two variables or values, whereas the greater-than ( > ) symbol instructs PHP to compare two values.

PHP operators are grouped as follows:

• Arithmetic operators
• Assignment operators
• Comparison operators
• Increment/Decrement operators
• Logical operators
• String operators
• Array operators
• Conditional assignment operators

Arithmetic Operators

The PHP arithmetic operators are used in conjunction with numeric values to perform common arithmetic operations such as addition, subtraction, multiplication, and so on.

Sample usage of Arithmetic Operators:

Assignment Operators

Assignment operators are used to assign values to variables.

Sample usage of Assignment Operators:

Comparison Operators

Comparison operators are used to compare two values in a Boolean fashion.

Sample usage of Comparison Operators:

Increment / Decrement Operators

Increment operators are used to increment a variable's value while decrement operators are used to decrement.

Sample usage of Increment / Decrement Operators:

Logical Operators

Logical operators are typically used to combine conditional statements.

Sample usage of Logical Operators:

String Operators

String operators are specifically designed for strings.

Sample usage of String Operators:

Array Operators

Array operators are used to compare arrays.

Conditional Assignment Operators

Conditional assignment operators are used to set a value depending on conditions.

Sample usage of Conditional Assignment Operators:

Create the following variables: $num1 , $num2 , $num3 . Assign the integer 3 to $num1 and 9 to $num2 . Multiply $num1 by $num2 and assign the product to $num3 . Print the result on $num3

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String Operators

There are two string operators. The first is the concatenation operator ('.'), which returns the concatenation of its right and left arguments. The second is the concatenating assignment operator (' .= '), which appends the argument on the right side to the argument on the left side. Please read Assignment Operators for more information.

<?php $a = "Hello " ; $b = $a . "World!" ; // now $b contains "Hello World!" $a = "Hello " ; $a .= "World!" ; // now $a contains "Hello World!" ?>

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Home » PHP Tutorial » PHP Null Coalescing Operator

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.

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Boolean assignment operators in PHP

I find myself doing this kind of thing somewhat often:

With bitwise operators, you can use the &= and |= shorthand:

Given that bitwise operations on 1 and 0 are functionally equivalent to boolean operations on true and false , we can rely on type-casting and do something like this:

...but that's pretty ugly and defeats the purpose of using a shorthand assignment syntax, since we have to use another statement to get the type back to boolean.

What I'd really like to do is something like this:

...but &&= and ||= are not valid operators, obviously. So, my question is - is there some other sugary syntax or maybe an obscure core function that might serve as a stand-in? With variables as short as $foo , it's not a big deal to just use $foo = $foo && false syntax, but array elements with multiple dimensions, and/or object method calls can make the syntax quite lengthy.

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• What is wrong with $foo = $foo && false;? Or is it just curiosity? –  Dany Caissy Commented Jul 9, 2013 at 16:08
• 2 @DanyCaissy: I explained in the last paragraph. There's nothing wrong with it; it's just that that syntax is redundant, and can get very lengthy (e.g. $some['big']['long']['variable'] = $some['big']['long']['variable'] && $some['other']['boolean']; ). –  FtDRbwLXw6 Commented Jul 9, 2013 at 16:10
• You may want to change your examples. Logically, these will always yield the same result = $foo &= false; and $foo &&= false; for $foo = true . So I'm failing to see the problem/goal. –  Jason McCreary Commented Jul 9, 2013 at 16:19
• 2 @JasonMcCreary: It depends on your definition of "same." As my examples point out, the former yields int(0) and the latter yields bool(false) . So while 0 == false because of implicit type-casting, 0 !== false . –  FtDRbwLXw6 Commented Jul 9, 2013 at 16:50
• This is still relevent 7 years latter with PHP7/8 type enforcement checks. Very easy to accidentally convert from a bool to an int if you use short syntax. –  evo_rob Commented Apr 6, 2021 at 11:26

3 Answers 3

In a way you have answered your own question:

bitwise operations on 1 and 0 are functionally equivalent to boolean operations on true and false

Bearing in mind that PHP is a weakly typed language, so it is not necessary to typecast to and from strict boolean values as 1 and 0 are equivalent to true and false (except strict equality, see below).

Consider the following code, using your examples:

Given PHP's implicit type juggling , falsy values , and with the exception of strict equaltiy , I'm hard pressed to see where such shorthand operations of &&= and ||= would not yield the same result as &= and |= . Especially when evaluating boolean values . It's likely why such shorthands don't exist in PHP.

Some quick benchmarks prove these are indeed equivalent, except for truthy arrays/objects:

• 1 You're correct, but I was actually looking for a solution that didn't change the type (hence why my 3rd example was explicitly type-casting back into a bool ). I have control over both the operands, and they're guaranteed to be bool s, so I'd much rather just use the longer syntax than potentially introduce errors into the code by returning "falsy" values instead of a strict bool like the interface has documented. –  FtDRbwLXw6 Commented Jul 9, 2013 at 17:00
• 1 Fair. Even though PHP is a weakly typed, dynamic language, I support writing such explicit code. My answer is based on that fact that for boolean values (and most other simple types) bitwise operators are equivalent to boolean operators. But if you want to use such a shorthand, you have to give up strict equality checks (or compare to 0/1). In the end, I don't really see the point. Nonetheless, I wanted to provide an answer for future readers. –  Jason McCreary Commented Jul 9, 2013 at 17:24
• Keep in mind, you could always cast it before returning the value. Probably good practice anyway. –  Jason McCreary Commented Jul 9, 2013 at 17:45
• 1 @JasonMcCreary No, boolean and bitwise operators are not equivalent, though their output is. The big difference is, that PHP does not even execute an expression for boolean operates if the outcome makes no difference. So $res = sql_query() OR die(); is not equivalent to $res = sql_query(); $res |= die(); . –  Matteo B. Commented Mar 25, 2015 at 11:45
• 1 @Matmarbon, correct, in these comments I forgot a key qualifier - functionally equivalent. –  Jason McCreary Commented Mar 25, 2015 at 12:57

As Jason mentioned, bitwise operators will work and it will not be necessary to convert the result back to boolean, as PHP will already handle their value as a boolean properly.

If you want an alternative that does not use bitwise operators, for the sake of readability or if you want strict equality, you can use this method :

Which means, you could change this :

It would also work with multiple conditions :

• 2 While helpful, it seems the OP is looking for something native and aware they can write custom code. –  Jason McCreary Commented Jul 9, 2013 at 16:22
• 1 I don't think there is something native that would do it for them, this is why I put this here. I'll remove my answer if I am proven wrong. While I'm sure OP could have came up with this method by himself, future readers that are less experienced might find it useful. –  Dany Caissy Commented Jul 9, 2013 at 16:23
• Did someone thing to post this to the PHP dev team? –  theking2 Commented Apr 6, 2022 at 12:00
• I did: on github –  theking2 Commented Apr 6, 2022 at 12:09

Right, &&= and ||= operators are indeed missing in PHP because bitwise operators can not be used as a replacement (without casting).

Here is an example you would expect to return true but returns false :

The missing &&= operator would return true because 1 && 10 = true

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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.