type GridColumns = [`Fixed(i64), `Fluid(f64)];
type GridHeight = [`AspectRatio(f64), `EvenlyDistribute(Length)];
type Grid = {
children: &Array<Widget>,
spacing: &f64,
columns: &GridColumns,
width: &[f64, null],
height: &GridHeight
};
val grid: fn(
?#spacing: &f64,
?#columns: &GridColumns,
?#width: &[f64, null],
?#height: &GridHeight,
children: &Array<Widget>
) -> Widget