protected function collectDoubledColumns(array $row)
    {
        $foundNames = [];
        $doubledColumns = [];

        foreach ($row as $column) {

            if (isset($foundNames[$column])) {
                $doubledColumns[] = $column;
            }
            $foundNames[$column] = true;
        }

        return $doubledColumns;
    }
protected function collectDoubledColumns(array $row)
    {
        $foundNames = [];
        $doubledColumns = [];

        foreach ($row as $column) {

            if (isset($foundNames[$column])) {
                $doubledColumns[] = $column;
            }
            $foundNames[$column] = true;
        }

        return $doubledColumns;
    }
protected function collectDoubledColumns ( array $ row ) { $ foundNames = [ ] ; $ doubledColumns = [ ] ; foreach ( $ row as $ column ) { if ( isset ( $ foundNames [ $ column ] ) ) { $ doubledColumns [ ] = $ column ; } $ foundNames [ $ column ] = true ; } return $ doubledColumns ; }
Collects double column names for better error messages

@param array $row

@return array
Collects double column names for better error messages