Function rustc_middle::mir::spanview::write_next_viewable_with_overlaps

fn write_next_viewable_with_overlaps<'tcx, 'b, W>(
    tcx: TyCtxt<'tcx>,
    from_pos: BytePos,
    to_pos: BytePos,
    ordered_viewables: &'b [SpanViewable],
    alt: bool,
    layer: usize,
    w: &mut W
) -> Result<(BytePos, &'b [SpanViewable])>where
    W: Write,

Recursively process each ordered span. Spans that overlap will have progressively varying styles, such as increased padding for each overlap. Non-overlapping adjacent spans will have alternating style choices, to help distinguish between them if, visually adjacent. The layer is incremented for each overlap, and the alt bool alternates between true and false, for each adjacent non-overlapping span. Source code between the spans (code that is not in any coverage region) has neutral styling.