Module value 

The IFC value model — serialization-independent.

Why this lives in ifc-model, not in a codec

IFC data arrives as STEP/SPF, ifcXML, and prospectively IFC-JSON. If the value type belonged to the STEP codec, every other codec would need its own parallel value type and cross-format conversion would be lossy by construction. The data model owns the values; codecs only translate.

Owned, not borrowed

Values own their data rather than borrowing from an mmap. A model must outlive the bytes it was read from — otherwise it cannot be mutated and written back, which is the entire point of round-tripping.

Structs

EntityId

An entity’s identifier as it appeared in the file (#42 → 42).

Enums

Value

One attribute slot in an entity.