Function object_drop_elide 

fn object_drop_elide(cx: &CapCtx) -> Support

The object site’s DropElide rule, in guard order: facts about the stream before facts about the object.

On a subgroup stream, the header’s subgroup-ID mode first (a reserved mode says something different about the wire than a first-object mode does), then whether eliding this object would redefine the subgroup ID. The status guard is last and applies on every draft and every stream kind.

A fetch stream reaches only the status guard, on every draft. Nothing about a fetch object’s own bytes can stop a removal: the framer pays for one by re-encoding the survivor’s framing against the frame that is now in front of it. The subgroup guards below are skipped rather than answered, because a fetch object states its own Subgroup ID or states that it has none, so eliding this would redefine the subgroup ID is not a sentence about it.