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<?php interface ChildVisitor { /* some visiting methods */ } interface ParentVisitor extends ChildVisitor { /* some extra visiting methods */ } interface ParentType { public function accept(ParentVisitor $visitor) : mixed; } interface ChildType extends ParentType { public function accept(ChildVisitor $visitor) : mixed; } interface OtherInterface extends ParentType {} interface InterfaceOrClass extends OtherInterface,ChildType {}
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Fatal error: Declaration of ParentType::accept(ParentVisitor $visitor): mixed must be compatible with ChildType::accept(ChildVisitor $visitor): mixed in /in/pLcNM on line 9
Process exited with code 255.
Output for 7.4.0 - 7.4.33
Warning: Declaration of ParentType::accept(ParentVisitor $visitor): mixed should be compatible with ChildType::accept(ChildVisitor $visitor): mixed in /in/pLcNM on line 9
Output for 7.3.0 - 7.3.33
Fatal error: Declaration of ChildType::accept(ChildVisitor $visitor): mixed must be compatible with ParentType::accept(ParentVisitor $visitor): mixed in /in/pLcNM on line 12
Process exited with code 255.

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