1 | <?php |
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15 | class IteratorApplySalesman |
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16 | { |
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17 | |||
18 | /** |
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19 | * @var Callable |
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20 | */ |
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21 | public $salesman_factory; |
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22 | |||
23 | |||
24 | /** |
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25 | * @var Callable |
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26 | */ |
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27 | public $apply; |
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28 | |||
29 | |||
30 | /** |
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31 | * @param callable $salesman_factory Callable that takes a Salesman ID and returns a Salesman instance. |
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32 | * @param SalesmanInterface $salesman_fallback Optional SalesmanInterface fallback instance |
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33 | * @param callable $apply Optional Callable that takes the current item on iteration. |
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34 | */ |
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35 | public function __construct( callable $salesman_factory, SalesmanInterface $salesman_fallback = null, callable $apply = null ) |
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40 | |||
41 | |||
42 | /** |
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43 | * Must return TRUE, according to PHP's iterator_applay. |
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44 | * |
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45 | * @see http://php.net/manual/de/function.iterator-apply.php |
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46 | */ |
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47 | public function __invoke( \Traversable $iterator ) |
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61 | |||
62 | |||
63 | } |
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64 |
Let’s take a look at an example:
In the above example, the authenticate() method works fine as long as you just pass instances of MyUser. However, if you now also want to pass a different implementation of User which does not have a getDisplayName() method, the code will break.
Available Fixes
Change the type-hint for the parameter:
Add an additional type-check:
Add the method to the interface: