Duplicate code is one of the most pungent code smells. A rule that is often used is to re-structure code once it is duplicated in three or more places.
Common duplication problems, and corresponding solutions are:
1 | <?php |
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12 | class Telephone |
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13 | { |
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14 | //Telephone variations |
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15 | protected $format_E164; |
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16 | protected $format_international; |
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17 | protected $format_national; |
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18 | protected $format_RFC3966; |
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19 | |||
20 | //Telephone structure |
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21 | protected $country_code; |
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22 | protected $area_code; |
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23 | protected $subscriber_code; |
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24 | protected $extension; |
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25 | |||
26 | //Telephone extras |
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27 | protected $region; |
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28 | protected $input; |
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29 | |||
30 | //Telephone types |
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31 | protected $typeMap = [ |
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32 | Type::FIXED_LINE => 'FIXED_LINE', |
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33 | Type::MOBILE => 'MOBILE', |
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34 | Type::FIXED_LINE_OR_MOBILE => 'FIXED_LINE_OR_MOBILE', |
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35 | Type::TOLL_FREE => 'TOLL_FREE', |
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36 | Type::PREMIUM_RATE => 'PREMIUM_RATE', |
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37 | Type::SHARED_COST => 'SHARED_COST', |
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38 | Type::VOIP => 'VOIP', |
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39 | Type::PERSONAL_NUMBER => 'PERSONAL_NUMBER', |
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40 | Type::PAGER => 'PAGER', |
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41 | Type::UAN => 'UAN', |
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42 | Type::UNKNOWN => 'UNKNOWN', |
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43 | Type::EMERGENCY => 'EMERGENCY', |
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44 | Type::VOICEMAIL => 'VOICEMAIL', |
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45 | Type::SHORT_CODE => 'SHORT_CODE', |
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46 | Type::STANDARD_RATE => 'STANDARD_RATE', |
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47 | ]; |
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48 | |||
49 | /** |
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50 | * @param string $input The phone number |
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51 | * @param string $region The region or country of the phone number |
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52 | */ |
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53 | 6 | public function __construct($input,$region = 'US') |
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59 | |||
60 | /** |
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61 | * @return void |
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62 | */ |
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63 | 6 | protected function setup() |
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84 | |||
85 | 6 | View Code Duplication | protected function extractAreaCode() |
97 | |||
98 | 6 | View Code Duplication | protected function extractSubscriberCode() |
110 | |||
111 | /*===================================== |
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112 | = Ouput Methods = |
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113 | =====================================*/ |
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114 | |||
115 | /** |
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116 | * @return string |
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117 | */ |
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118 | 3 | public function getRFC3966() |
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122 | |||
123 | /** |
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124 | * @return string |
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125 | */ |
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126 | 3 | public function getNational() |
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130 | |||
131 | /** |
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132 | * @return string |
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133 | */ |
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134 | 3 | public function getInternational() |
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138 | |||
139 | /** |
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140 | * @return string |
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141 | */ |
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142 | 3 | public function getE164() |
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146 | |||
147 | |||
148 | /** |
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149 | * @return string |
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150 | */ |
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151 | 3 | public function getOriginal() |
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155 | |||
156 | /** |
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157 | * @return string |
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158 | */ |
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159 | 3 | public function getAreaCode() |
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163 | |||
164 | /** |
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165 | * @return string |
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166 | */ |
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167 | 3 | public function getCountryCode() |
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171 | |||
172 | /** |
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173 | * @return string |
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174 | */ |
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175 | 3 | public function getSubscriberCode() |
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179 | |||
180 | /** |
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181 | * @return string |
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182 | */ |
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183 | 3 | public function getType() |
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187 | |||
188 | /** |
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189 | * @return string |
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190 | */ |
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191 | 6 | public function isValid() |
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195 | |||
196 | /** |
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197 | * @return string |
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198 | */ |
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199 | 3 | public function __toString() |
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203 | |||
204 | /*===== End of Ouput Methods ======*/ |
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205 | } |
In PHP it is possible to write to properties without declaring them. For example, the following is perfectly valid PHP code:
Generally, it is a good practice to explictly declare properties to avoid accidental typos and provide IDE auto-completion: