Function write_debug_heading

pub fn write_debug_heading<WriteT, WriteNestedT>(
    heading: &str,
    writer: &mut WriteT,
    context: &DebugContext<'_>,
    write_nested: WriteNestedT,
) -> Result<()>
where
    WriteT: Write,
    WriteNestedT: Fn(&mut WriteT, &DebugContext<'_>) -> Result<()>,

Write debug heading.