What happens if the value on the left side of the null coalescing operator is not null?
The null coalescing operator (??) in PHP is used to assign a default value to a variable if the value on the left side of the operator is null. However, if the value on the left side is not null, the operator does not have any effect on the variable.
When the value on the left side of the null coalescing operator is not null, the variable retains its original value. The operator simply evaluates the expression on the left side and returns it without any modification.
To understand this better, let's consider an example:
php $name = "John"; $defaultName = "Guest"; $result = $name ?? $defaultName;
In this example, the variable `$name` has a value of "John", which is not null. The null coalescing operator is used to assign a default value of "Guest" to the variable `$result` if `$name` is null. However, since `$name` is not null, the value of `$result` remains unchanged as "John".
Similarly, if the value on the left side of the null coalescing operator is an empty string, zero, or any other non-null value, the operator does not have any effect on the variable. The variable retains its original value.
php $number = 10; $defaultNumber = 0; $result = $number ?? $defaultNumber;
In this example, the variable `$number` has a value of 10, which is not null. The null coalescing operator is used to assign a default value of 0 to the variable `$result` if `$number` is null. However, since `$number` is not null, the value of `$result` remains unchanged as 10.
If the value on the left side of the null coalescing operator is not null, the operator does not have any effect on the variable. The variable retains its original value. The null coalescing operator is only used to assign a default value when the left side is null.
Other recent questions and answers regarding Examination review:
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