| 1 |  |  | <?php | 
            
                                                                                                            
                            
            
                                    
            
            
                | 2 |  |  | declare(strict_types=1); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 3 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 4 |  |  | namespace Wszetko\Sitemap\Items\DataTypes; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 5 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 6 |  |  | use Wszetko\Sitemap\Interfaces\DataType; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 7 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 8 |  |  | /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 9 |  |  |  * Class FloatType | 
            
                                                                                                            
                            
            
                                    
            
            
                | 10 |  |  |  * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 11 |  |  |  * @package Wszetko\Sitemap\Items\DataTypes | 
            
                                                                                                            
                            
            
                                    
            
            
                | 12 |  |  |  */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 13 |  |  | class FloatType extends AbstractDataType | 
            
                                                                                                            
                            
            
                                    
            
            
                | 14 |  |  | { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 15 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 16 |  |  |      * @var int|float | 
            
                                                                                                            
                            
            
                                    
            
            
                | 17 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 18 |  |  |     private $minValue; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 19 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 20 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 21 |  |  |      * @var int|float | 
            
                                                                                                            
                            
            
                                    
            
            
                | 22 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 23 |  |  |     private $maxValue; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 24 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 25 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 26 |  |  |      * @var int | 
            
                                                                                                            
                            
            
                                    
            
            
                | 27 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 28 |  |  |     protected $precision = null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 29 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 30 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 31 |  |  |      * @return float|null | 
            
                                                                                                            
                                                                
            
                                    
            
            
                | 32 |  |  |      */ | 
            
                                                                        
                            
            
                                    
            
            
                | 33 | 7 |  |     public function getMinValue(): ?float | 
            
                                                                        
                            
            
                                    
            
            
                | 34 |  |  |     { | 
            
                                                                        
                            
            
                                    
            
            
                | 35 | 7 |  |         return $this->minValue; | 
            
                                                                        
                            
            
                                    
            
            
                | 36 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 37 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 38 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 39 |  |  |      * @param float $minValue | 
            
                                                                                                            
                            
            
                                    
            
            
                | 40 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 41 |  |  |      * @return \Wszetko\Sitemap\Items\DataTypes\FloatType | 
            
                                                                                                            
                            
            
                                    
            
            
                | 42 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 43 | 33 |  |     public function setMinValue(float $minValue): self | 
            
                                                                                                            
                            
            
                                    
            
            
                | 44 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 45 | 33 |  |         $this->minValue = $minValue; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 46 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 47 | 33 |  |         return $this; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 48 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 49 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 50 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 51 |  |  |      * @return float|null | 
            
                                                                                                            
                            
            
                                    
            
            
                | 52 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 53 | 7 |  |     public function getMaxValue(): ?float | 
            
                                                                                                            
                            
            
                                    
            
            
                | 54 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 55 | 7 |  |         return $this->maxValue; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 56 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 57 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 58 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 59 |  |  |      * @param float $maxValue | 
            
                                                                                                            
                            
            
                                    
            
            
                | 60 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 61 |  |  |      * @return \Wszetko\Sitemap\Items\DataTypes\FloatType | 
            
                                                                                                            
                            
            
                                    
            
            
                | 62 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 63 | 33 |  |     public function setMaxValue(float $maxValue): self | 
            
                                                                                                            
                            
            
                                    
            
            
                | 64 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 65 | 33 |  |         $this->maxValue = $maxValue; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 66 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 67 | 33 |  |         return $this; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 68 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 69 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 70 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 71 |  |  |      * @return int|null | 
            
                                                                                                            
                            
            
                                    
            
            
                | 72 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 73 | 7 |  |     public function getPrecision(): ?int | 
            
                                                                                                            
                            
            
                                    
            
            
                | 74 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 75 | 7 |  |         return $this->precision; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 76 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 77 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 78 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 79 |  |  |      * @param int $precision | 
            
                                                                                                            
                            
            
                                    
            
            
                | 80 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 81 |  |  |      * @return \Wszetko\Sitemap\Items\DataTypes\FloatType | 
            
                                                                                                            
                            
            
                                    
            
            
                | 82 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 83 | 33 |  |     public function setPrecision(int $precision): self | 
            
                                                                                                            
                            
            
                                    
            
            
                | 84 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 85 | 33 |  |         $this->precision = $precision; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 86 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 87 | 33 |  |         return $this; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 88 |  |  |     } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 89 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 90 |  |  |     /** | 
            
                                                                                                            
                            
            
                                    
            
            
                | 91 |  |  |      * @param int|float|string|null $value | 
            
                                                                                                            
                            
            
                                    
            
            
                | 92 |  |  |      * @param array                 $parameters | 
            
                                                                                                            
                            
            
                                    
            
            
                | 93 |  |  |      * | 
            
                                                                                                            
                            
            
                                    
            
            
                | 94 |  |  |      * @return \Wszetko\Sitemap\Interfaces\DataType | 
            
                                                                                                            
                            
            
                                    
            
            
                | 95 |  |  |      */ | 
            
                                                                                                            
                            
            
                                    
            
            
                | 96 | 7 |  |     public function setValue($value, ...$parameters): DataType | 
            
                                                                                                            
                            
            
                                    
            
            
                | 97 |  |  |     { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 98 | 7 |  |         if (is_null($value)) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 99 | 1 |  |             $this->value = null; | 
            
                                                                                                            
                            
            
                                    
            
            
                | 100 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 101 | 1 |  |             return $this; | 
                            
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                | 102 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 103 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 104 | 7 |  |         if (is_string($value)) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 105 | 3 |  |             if (is_numeric($value)) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 106 | 3 |  |                 $value = floatval($value); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 107 |  |  |             } else { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 108 | 3 |  |                 return $this; | 
                            
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                | 109 |  |  |             } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 110 | 7 |  |         } elseif (!is_numeric($value)) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 111 | 3 |  |             return $this; | 
                            
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                | 112 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 113 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 114 | 7 |  |         if ($this->getMinValue() !== null && $value < $this->getMinValue()) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 115 | 3 |  |             return $this; | 
                            
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                | 116 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 117 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 118 | 7 |  |         if ($this->getMaxValue() !== null && $value > $this->getMaxValue()) { | 
            
                                                                                                            
                            
            
                                    
            
            
                | 119 | 3 |  |             return $this; | 
                            
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                | 120 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 121 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 122 | 7 |  |         if ($this->getPrecision()) { | 
                            
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                | 123 | 5 |  |             $value = round($value, $this->getPrecision()); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 124 | 5 |  |             $value = number_format($value, $this->getPrecision(), '.', ''); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 125 |  |  |         } | 
            
                                                                                                            
                            
            
                                    
            
            
                | 126 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 127 | 7 |  |         parent::setValue($value, $parameters[0]); | 
            
                                                                                                            
                            
            
                                    
            
            
                | 128 |  |  |  | 
            
                                                                                                            
                            
            
                                    
            
            
                | 129 | 7 |  |         return $this; | 
                            
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                | 130 |  |  |     } | 
            
                                                        
            
                                    
            
            
                | 131 |  |  | } | 
            
                        
If you return a value from a function or method, it should be a sub-type of the type that is given by the parent type f.e. an interface, or abstract method. This is more formally defined by the Lizkov substitution principle, and guarantees that classes that depend on the parent type can use any instance of a child type interchangably. This principle also belongs to the SOLID principles for object oriented design.
Let’s take a look at an example:
Our function
my_functionexpects aPostobject, and outputs the author of the post. The base classPostreturns a simple string and outputting a simple string will work just fine. However, the child classBlogPostwhich is a sub-type ofPostinstead decided to return anobject, and is therefore violating the SOLID principles. If aBlogPostwere passed tomy_function, PHP would not complain, but ultimately fail when executing thestrtouppercall in its body.