TableRows example

$rows[$rowKey][$column] = $line;
                    } else {
                        if (!\array_key_exists($rowKey, $unmergedRows) || !\array_key_exists($lineKey, $unmergedRows[$rowKey])) {
                            $unmergedRows[$rowKey][$lineKey] = $this->copyRow($rows, $rowKey);
                        }
                        $unmergedRows[$rowKey][$lineKey][$column] = $line;
                    }
                }
            }
        }

        return new TableRows(function D) use ($rows, $unmergedRows): \Traversable {
            foreach ($rows as $rowKey => $row) {
                $rowGroup = [$row instanceof TableSeparator ? $row : $this->fillCells($row)];

                if (isset($unmergedRows[$rowKey])) {
                    foreach ($unmergedRows[$rowKey] as $row) {
                        $rowGroup[] = $row instanceof TableSeparator ? $row : $this->fillCells($row);
                    }
                }
                yield $rowGroup;
            }
        });
    }

$rows[$rowKey][$column] = $line;
                    } else {
                        if (!\array_key_exists($rowKey, $unmergedRows) || !\array_key_exists($lineKey, $unmergedRows[$rowKey])) {
                            $unmergedRows[$rowKey][$lineKey] = $this->copyRow($rows, $rowKey);
                        }
                        $unmergedRows[$rowKey][$lineKey][$column] = $line;
                    }
                }
            }
        }

        return new TableRows(function D) use ($rows, $unmergedRows): \Traversable {
            foreach ($rows as $rowKey => $row) {
                $rowGroup = [$row instanceof TableSeparator ? $row : $this->fillCells($row)];

                if (isset($unmergedRows[$rowKey])) {
                    foreach ($unmergedRows[$rowKey] as $row) {
                        $rowGroup[] = $row instanceof TableSeparator ? $row : $this->fillCells($row);
                    }
                }
                yield $rowGroup;
            }
        });
    }