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<?php /* Challenge 2: Implement AnswerInterface and get Question to echo "4". */ class Question { public function __construct(AnswerInterface $answer) { echo "What is 2 + 2?\n"; $answer = $answer->get()->the()->answer(); if ($answer instanceof AnswerInterface) { echo $answer . PHP_EOL; } } } interface AnswerInterface { public function get(); public function the(); public function answer(); } // start editing here class Answer implements AnswerInterface { public function __construct() { echo "Trace..."; } public function get() { return new Answer();} public function the() { return new Answer();} public function answer() { return 4;} } // end editing here $answer = new Answer; $question = new Question($answer);
Output for 5.2.14 - 5.2.17, 5.3.3 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
Trace...What is 2 + 2? Trace...Trace...
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.13, 5.3.0 - 5.3.2
Strict Standards: Redefining already defined constructor for class Answer in /in/nC9HO on line 34 Trace...What is 2 + 2? Trace...Trace...
Output for 4.4.2 - 4.4.9
Parse error: syntax error, unexpected T_STRING, expecting T_OLD_FUNCTION or T_FUNCTION or T_VAR or '}' in /in/nC9HO on line 9
Process exited with code 255.
Output for 4.3.0 - 4.3.1, 4.3.5 - 4.3.11, 4.4.0 - 4.4.1
Parse error: parse error, unexpected T_STRING, expecting T_OLD_FUNCTION or T_FUNCTION or T_VAR or '}' in /in/nC9HO on line 9
Process exited with code 255.
Output for 4.3.2 - 4.3.4
Parse error: parse error, expecting `T_OLD_FUNCTION' or `T_FUNCTION' or `T_VAR' or `'}'' in /in/nC9HO on line 9
Process exited with code 255.

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