Bug #74350 [Com]: defined() not working for $objectinstance::CLASS_CONSTANT

Edit report at https://bugs.php.net/bug.php?id=74350&edit=1 ID: 74350 Comment by: Andy_Schmidt at HM-Software dot com Reported by: Andy_Schmidt at HM-Software dot com Summary: defined() not working for $objectinstance::CLASS_CONSTANT Status: Not a bug Type: Bug Package: Class/Object related Operating System: Windows PHP Version: 7.1.3 Block user comment: N Private report: N New Comment: Yes, I am aware how to circumvent this by obtaining the class first. However, the point is: defined( 'Class_A::CONST_A' ) >>> WORKS defined( $class_name.'::CONST_A' ) >>> WORKS defined( "$class_name::CONST_A" ) >>> WORKS But, I have found no working syntax for $object. That seems counter-intuitive, considering echo $object_A::CONST_A; >>> WORKS so "defined()" should represent that correct state. PS - I do appreciate the dilemma presented by string substitution, object to string conversion etc. in this particular context. Previous Comments: ------------------------------------------------------------------------ [2017-03-31 18:03:24] peehaa@php.net The reason you get "not" defined! is because the instance is within single quotes. Which means it will mean a literal $object_A because normal string rules apply. You can always do: if ( defined( get_class($object_A) . '::CONST_A' ) ) to get what you want. ------------------------------------------------------------------------ [2017-03-31 17:50:06] Andy_Schmidt at HM-Software dot com Description: ------------ defined() will function correctly for class constants, if either the class name or a classname variable is used. However, if one tries to check the existence of a constant of the class that was used to instantiate the object, then it will return "not defined". Test script: --------------- class Class_A { const CONST_A = 'value A'; // CONST_B not defined } $class_name = Class_A::class; $object_A = new $class_name(); // Class references work correctly! if ( defined( 'Class_A::CONST_A' ) ) echo 'Class_A::CONST_A defined'; if ( defined( $class_name.'::CONST_A' ) ) echo '$class_name::CONST_A defined'; if ( !defined( 'Class_A::CONST_B' ) ) echo 'No Class_A::CONST_B'; if ( !defined( $class_name.'::CONST_B' ) ) echo 'No $class_name::CONST_B'; echo $object_A::CONST_A; // As expected, result: "value A" ! **** // ***** Yet, using that object reference will report "not" defined! ***** if ( defined( '$object_A::CONST_A' ) ) echo '$object_A::CONST_A defined !!'; else echo 'no $object_A::CONST_A'; // PS: As expected, "Fatal Error: Object of class Class_A could not be converted to string" if ( defined( "$object_A::CONST_A" ) ) echo 'Should cause error, and does'; if ( defined( $object_A.'::CONST_A' ) ) echo 'Should cause error, and does'; Expected result: ---------------- Class_A::CONST_A defined $class_name::CONST_A defined No Class_A::CONST_B No $class_name::CONST_B value A $object_A::CONST_A defined!! Actual result: -------------- Class_A::CONST_A defined $class_name::CONST_A defined No Class_A::CONST_B No $class_name::CONST_B value A no $object_A::CONST_A ------------------------------------------------------------------------ -- Edit this bug report at https://bugs.php.net/bug.php?id=74350&edit=1