PHP

How to avoid undefined property errors with Null Coalescing operator

Thursday April 3, 2025

If an object has an optional property, we can use ?? to avoid undefined property errors.

We use ?? to avoid undefined property errors.
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Here, we set a default value since the property $email is null by default.

Had we not used the Null Coalescing operator, we would get an Uncaught Error.

Without using the Null Coalescing operator, we get an Uncaught Error
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Accessing Nested Object Properties

If we’re certain that all objects exist, you can access nested properties using the object operator (->).

Example of accessing nested properties using the object operator.
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A null property would trigger a Warning.

In the previous example, a null property would trigger a Warning.
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In order to access nested PHP objects without triggering errors we can use the Null Coalescing operator.

Example of accessing nested PHP objects with the use the Null Coalescing operator
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Using Null Coalescing with Method Calls

Another usecase for the Null Coalescing operator is with method calls.

Example of Null Coalescing operator used with a method.
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If a method might return null, we can use ?? to set a default.

We anticipate errors with methods returning nullish values with Null Coalescing.
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