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Error Identifier: trait.nameInUse

Every error reported by PHPStan has an error identifier. Here’s a list of all error identifiers. In PHPStan Pro you can see the error identifier next to each error and filter errors by their identifiers.

Code example #

<?php

namespace App;

use SomeLibrary\Helper;

trait Helper
{
}

Why is it reported? #

A trait is being declared with a name that is already in use within the same namespace, typically because a use import statement has already introduced the same name. PHP does not allow two symbols with the same name in the same namespace scope, and this will cause a fatal error at runtime.

How to fix it #

Rename the trait to avoid the name conflict:

 <?php
 
 namespace App;

 use SomeLibrary\Helper;

-trait Helper
+trait AppHelper
 {
 }

Or alias the imported name to avoid the collision:

 <?php
 
 namespace App;

-use SomeLibrary\Helper;
+use SomeLibrary\Helper as LibraryHelper;

 trait Helper
 {
 }

Non-ignorable error #

This error cannot be ignored using @phpstan-ignore or the ignoreErrors configuration. Non-ignorable errors indicate code that would cause a crash or a fatal error at runtime, or a fundamental problem in the analysed code that must be addressed.

Rules that report this error #

  • PHPStan\Rules\Names\UsedNamesRule [1]

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