interval propagation: contradictions fail, finite ranges enumerate

1 files changed, 4 insertions, 3 deletions

diff --git a/docs/virtual-machine-specification.org b/docs/virtual-machine-specification.org
index c44b666..828bc3c 100644
--- a/docs/virtual-machine-specification.org
+++ b/docs/virtual-machine-specification.org
@@ -131,9 +131,10 @@ whole or not at all.
 Specified, not yet implemented; each grows admission or planning
 without changing admitted semantics:
 
-- constraint propagation: residuated constraints today wait and
-  return; a store that actively narrows domains and detects
-  unsatisfiable residue early is the next strength;
+- richer propagation: the interval store today reads domains and
+  one-sided comparisons; difference constraints between variables,
+  arithmetic relations, and propagation through record structure
+  are the next strengths;
 - symbolic discharge: algebraic evidence for universals over
   infinite domains, and arithmetic decrease measures for recursion
   that structural containment cannot see;