df.with { name.firstName }

Input DataFrame: rowsCount = 7, columnsCount = 5

Output DataFrame: rowsCount = 7, columnsCount = 5

df.with { col -> col.map { it?.lowercase() } }

Input DataFrame: rowsCount = 7, columnsCount = 5

Output DataFrame: rowsCount = 7, columnsCount = 5

df.with { 2021 - age named "year" }

Input DataFrame: rowsCount = 7, columnsCount = 5

Output DataFrame: rowsCount = 7, columnsCount = 5