ucum 0.9.0

UCUM (Unified Code for Units of Measure) for Dart — unit validation, conversion, and quantity arithmetic for healthcare. Port of the reference Java library.

0.9.0

Correctness release with breaking changes. All 660+ tests pass, including the full official UCUM functional suite and the downstream fhirpath (1069) and cql (595) suites.

Critical fixes

• Affine temperature conversions were silently wrong: convert(37, 'Cel', 'K') returned -10069.55 because the converter folded the affine offset into the multiplicative factor. Conversions now route through the ratio scale via SpecialUnitHandler.toRatio/fromRatio (ucum-lhc's functional-converter model): 37 Cel -> 310.15 K, 98.6 [degF] -> 37 Cel. Unit-level canonicalization of affine units throws, as Ucum-java does; getCanonicalForm(Pair) converts through K (the measurement value is available at the Pair level); compound/prefixed affine units (Cel/s, mCel) throw instead of mis-converting.
• The lexer hung forever on an unterminated annotation ('{...'); it now throws unterminated annotation.
• The unit data tables were unreproducible, stale (pre-2.2 essence, old Avogadro number), and contained 462 non-essence shadow units — 186 with empty definitions ('mcg' canonicalized to unity) and several corrupted codes. Data is now generated from ucum-essence 2.2 (2024-06-17) by the checked-in tool/generate_definitions.dart; [FNU]/[NTU] added; the essence version is exposed via ucumIdentification() and UcumModel.version.

Breaking: strict validation vs explicit resolution

• validate() and the parser are now spec-strict (Ucum-java parity): display names and plurals ('meter', 'seconds', 'mcg', 'inch') no longer validate. The new explicit UcumService.resolveCommonUnit + commonUnitSynonyms map provide the lenient path ('mcg' -> 'ug', including inside compounds: 'mcg/mL' -> 'ug/mL'). ValidatedQuantity resolves automatically, so '2.54 cm' == '1 inch' still works.
• ValidatedQuantity fixes: >/< with String operands now unit-convert (1 m > '50 cm' was false); >=/<= include equality for numeric operands (VQ(5) >= 5 was false); hashCode is canonical-form based and consistent with the unit-converting ==; numeric operands uniformly mean dimensionless '1' (CQL promotion rule); fromString no longer deletes digits inside units ('2 m2'); compareTo throws a clear UcumException for incomparable units.
• UcumDecimal: negative zero is normalized (-0 compared less than 0).
• Package layout: implementation moved under lib/src/ with a curated package:ucum/ucum.dart barrel — the lexer/parser/converter internals are no longer exported. Import the barrel only.
• Web/WASM support restored: the test-only dart:io XML helper left lib/, and xml is now a dev dependency.
• SDK floor raised to ^3.5.0; added pub.dev topics; rewrote README and example against the real API.

0.8.0

• Fix +, -, % operators to convert units before arithmetic

0.7.0

• Fixed 6 unit definition data bugs (Bd, Oe, [S], [diop], [mesh_i], [mu_0])
• Fixed converter precision to use 24 significant digits consistently
• Removed deprecated lints from analysis_options.yaml
• Updated dependencies (xml ^6.6.1, lints ^6.1.0, test ^1.29.0)

0.6.0

• Added asDouble getter to UcumDecimal

0.5.0

• Fixed errors with doAdd in UcumDecimal

0.4.0

• More lints

0.3.0

• Just more linting updates

0.2.0

• Updates for linting errors
• I want my pub points

0.1.0

• First publication of this package for Dart
• Based on Java-ucum package