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PHP Object-Oriented PHP Basics Building a Collection Shopping List Method

Justin Radcliffe
Justin Radcliffe
18,987 Points

I don't follow some of the logic - could someone clarify?

public function getCombinedIngredients() 
       $ingredients = [];
       foreach ($this->recipes as $recipe) {
           foreach ($recipe->getIngredients() as $ing) {
               $item = $ing['item'];
               // if item string contains a ','
               if (strpos($item, ',')) {
                   // select string BEFORE (using true boolean) the ',' (if i wanted AFTER the ',' don't use true boolean)
                   $item = strstr($item, ',', true);


               // if item is plural (contain an 's' on the end)
               if (in_array($item.'s', $ingredients)) {
                   $item .= 's';
               } elseif (in_array(substr($item, 0, -1), $ingredients)) {
                   $item = substr($item, 0, -1);


               $ingredients[$item] = [
       return $ingredients;

2 Answers

I feel lost for the exact same portion of the code. If anyone can explain it would be great!

The first part on the second part also is not clear to me, specifically "$item .= 's';"

The second part of that block seems like it filters plural items and only passes singular ingredients to $item