Represents a mutable grid of code points.
The height of this grid, i.e. the number of rows.
The width of this grid, i.e. the number of columns.
Gets the code point at the specified x and y coordinates.
Creates an IntSet of all code points in the grid, excluding 0 (null character).
Sets the code point at the specified x and y coordinates and resizes the grid if necessary.
Creates a list of strings representing the rows of this grid.