Function compareStrokes

compareStrokes(
a: IBorders.IStroke | null | undefined,
b: IBorders.IStroke | null | undefined,
): number
Orders two strokes that meet on the same shared edge — the bottom of one cell and the top of the cell below, or the right of one cell and the left of the next — by which one is drawn.
Parameters
- a: IBorders.IStroke | null | undefined
  A stroke on the shared edge.
- b: IBorders.IStroke | null | undefined
  The neighbor's stroke on the same edge.
Returns number
A positive number when a is drawn, negative when b is, 0 when they are interchangeable.

Remarks
Only one stroke is drawn on a shared edge, chosen as Excel chooses it: the heavier style wins, ranked hair < dashDotDot < dashDot < dotted < dashed < thin < mediumDashDotDot < slantDashDot < mediumDashDot < mediumDashed < medium < thick < double, and between two strokes of the same style the darker color wins. Any stroke wins over none.