TR-CORE-UNKNOWN / Teal / Review draft

Known zero and typed unknown

Terminology revised · September 12 evidence

Later individual Teal rerun. The reported execution status is historical and is not a new test result.

TEAL LIBRARY RERUN  |  12 SEPTEMBER 2026  |  Michael Patrick Bangel
3
TEAL-RERUN-03-B001 | RELATED_EXECUTION_EVIDENCE_AVAILABLE
TR-CORE-UNKNOWN / Known zero and typed unknown
IF
A value is absent, disputed or explicitly zero.
HOW
Carry missingness in the declared type; preserve zero as a known numeric value. Propagate unknown through
arithmetic and hold required unknown conditions.
THEN
A missing measurement remains missing. No default numeric zero may become observed evidence.
CURRENT EVIDENCE
Fresh related language/paper/water checks are in the evidence ledger. The test count is suite evidence, not
proof of every branch in this requirement.
REMAINING REQUIREMENT
Use the source and recorded case evidence to close remaining per-branch, native-host and full-contract coverage gaps.
SOURCE REFERENCES
bangel:language/python/src/bangel/values.py; bangel:language/python/src/bangel/strict_runtime.py;
bangel:language/python/src/bangel/ir_types.py; associated-core:reference/src/bangel/values.py;
associated-core:reference/src/bangel/strict_runtime.py; associated-core:reference/src/bangel/ir_types.py

Publication is pending owner review. White papers are excluded.