23 Extents

• Introduction to Extents: Extents are ranges over text, with properties.
• Extent Ordering: How extents are ordered internally.
• Format of the Extent Info: The extent information in a buffer or string.
• Zero-Length Extents: A weird special case.
• Mathematics of Extent Ordering: A rigorous foundation.
• Extent Fragments: Cached information useful for redisplay.