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                <?php  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                namespace Flugg\Responder\Transformers\Concerns;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                use Illuminate\Database\Eloquent\Model;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * A trait to be used by a transformer to handle relations  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * @package flugger/laravel-responder  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * @author  Alexander Tømmerås <[email protected]>  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 * @license The MIT License  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                 */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                trait HasRelationships  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * List of available relations.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @var string[]  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    protected $relations = [];  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * A list of autoloaded default relations.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @var array  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    protected $load = [];  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Get a list of whitelisted relations, including nested relations.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return array  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function whitelistedRelations(): array  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $nestedRelations = $this->getNestedRelations($this->relations, function ($transformer) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            return $transformer->whitelistedRelations();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        });  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return array_merge($this->normalizeRelations($this->relations), $nestedRelations);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Get a list of default relations, including nested relations.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return array  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    public function defaultRelations(): array  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $nestedRelations = $this->getNestedRelations($this->load, function ($transformer) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            return $transformer->defaultRelations();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        });  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return array_merge($this->normalizeRelations($this->load), $nestedRelations);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Extract a list of nested relations from the transformers provided in the  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * list of relations.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param  array    $relations  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param  callable $nestedCallback  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return array  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    protected function getNestedRelations(array $relations, callable $nestedCallback): array  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return collect($relations)->filter(function ($transformer, $relation) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            return ! is_numeric($relation) && ! is_null($transformer);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        })->map(function ($transformer) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            return $this->resolveTransformer($transformer);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        })->flatMap(function ($transformer, $relation) use ($nestedCallback) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            return collect($nestedRelations = $nestedCallback($transformer))  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                                ->keys()  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                                ->reduce(function ($value, $nestedRelation) use ($relation, $nestedRelations) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                                    return array_merge($value, ["$relation.$nestedRelation" => $nestedRelations[$nestedRelation]]);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                                }, []);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        })->all();  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Normalize relations to force a key value structure.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param  array $relations  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return array  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    protected function normalizeRelations(array $relations): array  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return collect(array_keys($relations))->reduce(function ($normalized, $relation) use ($relations) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            if (is_numeric($relation)) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                                $relation = $relations[$relation];  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            return array_merge($normalized, [$relation => $this->getQueryConstraint($relation)]);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }, []);  | 
            
            
                                                                                                            
                                                                
            
                                    
            
            
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                    }  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                        
                            
            
                                    
            
            
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                     * Normalize relations to force a key value structure.  | 
            
            
                                                                        
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                        
                            
            
                                    
            
            
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                     * @param  string $relation  | 
            
            
                                                                        
                            
            
                                    
            
            
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                     * @return \Closure|null  | 
            
            
                                                                        
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    protected function getQueryConstraint(string $relation)  | 
            
            
                                                                        
                            
            
                                    
            
            
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                    { | 
            
            
                                                                        
                            
            
                                    
            
            
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                        if (! method_exists($this, $method = 'load' . ucfirst($relation))) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            return null;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return function ($query) use ($method) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            return $this->$method($query);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        };  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Resolve a relationship from a model instance.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param  \Illuminate\Database\Eloquent\Model $model  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param  string                              $identifier  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @return mixed  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    protected function resolveRelation(Model $model, string $identifier)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        $relation = $model->$identifier;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        if (method_exists($this, $method = 'filter' . ucfirst($identifier))) { | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                            return $this->$method($relation);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                        return $relation;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * Get a related transformer class mapped to a relation identifier.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                     * @param  string $identifier  | 
            
            
                                                                                                            
                            
            
                                    
            
            
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                    137
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                                                     | 
                
                 | 
                     * @return string|null  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    138
                 | 
                                    
                                                     | 
                
                 | 
                     */  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    139
                 | 
                                    
                             10                          | 
                
                 | 
                    protected function getRelatedTransformerName(string $identifier)  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    140
                 | 
                                    
                                                     | 
                
                 | 
                    { | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    141
                 | 
                                    
                             10                          | 
                
                 | 
                        $relations = array_merge($this->relations, $this->load);  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    142
                 | 
                                    
                                                     | 
                
                 | 
                 | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    143
                 | 
                                    
                             10                          | 
                
                 | 
                        return array_has($relations, $identifier) ? $relations[$identifier] : null;  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    144
                 | 
                                    
                                                     | 
                
                 | 
                    }  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    145
                 | 
                                    
                                                     | 
                
                 | 
                 | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    146
                 | 
                                    
                                                     | 
                
                 | 
                    /**  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    147
                 | 
                                    
                                                     | 
                
                 | 
                     * Resolve a transformer from a class name string.  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    148
                 | 
                                    
                                                     | 
                
                 | 
                     *  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    149
                 | 
                                    
                                                     | 
                
                 | 
                     * @param  string $transformer  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    150
                 | 
                                    
                                                     | 
                
                 | 
                     * @return mixed  | 
            
            
                                                                                                            
                            
            
                                    
            
            
                | 
                    151
                 | 
                                    
                                                     | 
                
                 | 
                     */  | 
            
            
                                                                                                            
                                                                
            
                                    
            
            
                | 
                    152
                 | 
                                    
                                                     | 
                
                 | 
                    protected abstract function resolveTransformer(string $transformer);  | 
            
            
                                                        
            
                                    
            
            
                | 
                    153
                 | 
                                    
                                                     | 
                
                 | 
                }  |