public static PointF?PointForIndex <TFont, TGlyph>(
this FractionDisplay <TFont, TGlyph> self,
TypesettingContext <TFont, TGlyph> _,
MathListIndex index) where TFont : IFont <TGlyph> =>
index.SubIndexType != MathListSubIndexType.None
? throw new ArgumentException
("The subindex must be none to get the closest point for it.", nameof(index))
: index.AtomIndex == self.Range.End
// draw a caret after the fraction
? self.Position.Plus(new PointF(self.DisplayBounds().Right, 0))
// draw a caret before the fraction
: self.Position;
