True or False: In PHP 5.4 Traits can have properties?

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ANSWER:

True!

In PHP 5.4 Traits may contain properties as long as properties do not exist in the calling class. But beware, if the property already exists PHP will throw an error (fatal if the property isn’t identical to the trait property, and E_STRICT if it is).

PHP

trait demo { public $demo = 'this is a demo'; public $test = 'this is a test'; public function cool() { /* this is the method */ } /* ... */ }

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trait demo { public $demo = 'this is a demo'; public $test = 'this is a test'; public function cool() { /* this is the method */ } /* ... */ }

Valid

PHP

trait testTrait { public $demo = 'test'; } class testClass { use testTrait; function test() { echo $this->demo; } /* ... */ }

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trait testTrait { public $demo = 'test'; } class testClass { use testTrait; function test() { echo $this->demo; } /* ... */ }

E_STRICT Error

PHP

trait testTrait { public $demo = 'test'; } class testClass { use testTrait; public $demo = 'test'; /* ... */ }

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trait testTrait { public $demo = 'test'; } class testClass { use testTrait; public $demo = 'test'; /* ... */ }

Fatal Error:

PHP

trait testTrait { public $demo = 10; } class testClass { use testTrait; public $demo = 'test'; /* ... */ }

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trait testTrait { public $demo = 10; } class testClass { use testTrait; public $demo = 'test'; /* ... */ }

Fatal Error:

PHP

trait testTrait { public $demo = 'test'; } class testClass { use testTrait; protected $demo = 'test'; /* ... */ }

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trait testTrait { public $demo = 'test'; } class testClass { use testTrait; protected $demo = 'test'; /* ... */ }

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PHP Manual:
http://php.net/manual/en/language.oop5.traits.php