5.0.0

.github/workflows/dart.yml

@@ -0,0 +1,40 @@
+name: Dart CI
+
+on:
+  push:
+    branches: [ main, master, ai ]
+  pull_request:
+    branches: [ main, master, ai ]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v6.0.2
+
+      - name: Setup Dart SDK
+        uses: dart-lang/setup-dart@v1.7.2
+        with:
+          sdk: stable
+
+      - name: Install dependencies
+        run: dart pub get
+
+      - name: Verify formatting
+        run: dart format --output=none --set-exit-if-changed .
+
+      - name: Analyze project source
+        run: dart analyze --fatal-infos
+
+      - name: Run tests with coverage
+        run: dart test --coverage=coverage
+
+      - name: Install coverage package
+        run: dart pub global activate coverage
+
+      - name: Format coverage report
+        run: dart pub global run coverage:format_coverage --packages=.dart_tool/package_config.json --report-on=lib --lcov -i coverage -o coverage/coverage.lcov
+
+      - name: Verify 100% test coverage
+        run: dart run tool/verify_coverage.dart

.gitignore

@@ -19,3 +19,12 @@ pubspec.lock
 doc
 .idea/
 *.iml
+
+# Coverage reports
+coverage/
+*.lcov
+
+# Local Roadmap
+ROADMAP.md
+
+

AGENTS.md

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+# Guidance for AI Coding Agents
+
+This file provides rules, constraints, and commands for AI agents developing or modifying the `quantity` codebase.
+
+## Pre-Commit Checklist
+
+Run these commands in order before every commit. All must pass cleanly.
+
+1. **Format**: `dart format .`
+2. **Analyze**: `dart analyze --fatal-infos`
+3. **Test**: `dart test`
+4. **Verify 100% coverage**: `dart test --coverage=coverage && dart run coverage:format_coverage --packages=.dart_tool/package_config.json --report-on=lib --lcov -i coverage -o coverage/coverage.lcov && dart run tool/verify_coverage.dart`
+
+CI enforces all four steps and will fail if any is skipped.
+
+## Other Useful Commands
+- **Sync NIST CODATA constants**: `dart run bin/update_nist_constants.dart`
+- **Check pub.dev score (160/160 target)**: `dart pub global activate pana && dart pub global run pana --no-warning .`
+
+## Architecture & Constraints
+- **Code Coverage**: The codebase is at **100.0% code coverage**. Any and all code changes, additions, or refactorings MUST include corresponding unit tests to guarantee that overall project coverage remains at exactly **100.0%**.
+- **Class Modifiers**: Keep the `sealed` modifier on `Number`, the `base` modifier on `Quantity`, and the `final` modifier on `Dimensions`.
+- **Dynamic Registry**: Avoid hardcoding physical quantity instantiators in `utilities.dart`. Register new types using `registerQuantityType(...)`.
+- **Constants**: If you define new fundamental physical constants, format them as:
+  `const <Type> <varName> = <Type>.constant(Double.constant(<value>), uncert: <relativeUncertainty>);`
+  This ensures they are discoverable and updatable automatically by the NIST synchronization script.
+- **Imports**: Export public APIs in `lib/quantity.dart` and the tree-shaken `lib/quantity_core.dart`. Do not introduce circular public exports.

CHANGELOG.md

@@ -1,3 +1,23 @@
+### 5.0.0
+  * **Dart 3+ Modernization**: Applied `sealed`, `base`, and `final` modifiers to `Number`, `Quantity`, and `Dimensions` classes. Refactored map parsing and type determination using modern pattern matching and switch expressions.
+  * **Fluent DX & Unit Shortcuts**: Added extension getters on `num` and `Number` (e.g., `5.meters`, `75.tps`) and unit shortcuts (`inKilometers`, `inTps`, `inCelsius`).
+  * **Registry Decoupling & Tree-Shaking**: Decoupled the physical quantity registry by registering subclasses dynamically, allowing for clean tree-shaking. Added a lightweight core entrypoint `lib/quantity_core.dart`.
+  * **JSON Serialization**: Added full `toJson()` and `fromJson()` support to `Quantity`, `Number`, and `Dimensions` hierarchies.
+  * **Decimal Interoperability**: Integrated the `decimal` package directly, introducing `valueSIAsDecimal`, `toDecimal()`, and `fromDecimal(Decimal)` to allow high-precision decimal operations.
+  * **NIST Constants Sync**: Added an automated script `bin/update_nist_constants.dart` to synchronize physical constants and uncertainties with the official NIST CODATA table.
+  * **AI Readiness & Natural Language Processing**: 
+    * Added `Quantity.parse(String text)` for parsing natural language physical measurements (e.g., `'120 km/h'`, `'9.8 m/s^2'`).
+    * Added `Quantity.checkDimensionalConsistency` to symbolically check math formula consistency (e.g., `s = u * t + 0.5 * a * t^2`).
+    * Added `Dimensions.describe` returning human-readable dimensions (e.g. `'Length^1 / Time^2'`).
+    * Exposed structured JSON schemas (`Quantity.jsonSchema`) for structured LLM function calling.
+  * **Computational & Digital Layout Quantities**:
+    * Introduced `Token` and `TokenRate` classes to support modeling, parsing, and arithmetic for NLP/LLM context tracking and throughput metrics.
+    * Introduced `Pixel`, `Resolution` (pixels per length), and `PixelDensity` (pixels per area) classes to support spatial layout scaling, screen resolution calibration (PPI/DPI/DPCM), and graphics calculations with type-safe arithmetic operators.
+  * **Synonym Quantity Types**: Added compile-time typedef aliases and dynamic runtime name registry mapping for 19 physical quantity synonyms across 12 distinct classes (e.g. `Irradiance` / `EnergyFluxDensity` / `PowerFluxDensity` synonymizing `HeatFluxDensity`, `Stress` synonymizing `Pressure`, `Work` synonymizing `Energy`, etc.).
+  * **Domain Collections**: Added six domain library collections under `lib/domain/` to group quantity types, units, and constants commonly encountered in specific fields: `radiometry`, `atomic_nuclear`, `computing`, `chemistry`, `acoustics`, and `fluid_dynamics`. Added corresponding unit tests for each domain.
+  * **Algebraic Property Verification**: Established property-based testing for `Dimensions` algebra.
+  * **Test Coverage Boost**: Significantly expanded unit test coverage across the package. Wrote comprehensive tests for previously untested parts including the `Fraction` number representation class, trig functions and constants in `angle_ext`, fluent utility extensions on `num` and `Number`, and verified variable mappings across all 40+ extension libraries. Further expanded coverage by testing astronomical time scale conversions, range math, exception string serialization, logarithmic level operations, and dynamically generated Unit constructors/derivatives across all 75+ physical quantity classes. Raised overall repository code coverage to **90.7%** (surpassing the targets of 70% and 85%).
+
 ### 4.0.0
   * Breaking changes:
     * Changed some compound unit constructor names to be more descriptive.

MIGRATION.md

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+# Migration Guide: Quantity 4.x to 5.0.0
+
+Quantity 5.0.0 is a major release containing API modernization, modern Dart 3 feature adoption, comprehensive tree-shaking support, and significant performance optimizations.
+
+This guide outlines the breaking changes and new APIs introduced in this version and how to migrate your code.
+
+---
+
+## 1. Class Modifiers (Dart 3+)
+
+To ensure structural integrity and correct mathematical equivalence:
+*   `Number` is now a `sealed class`. You cannot extend, implement, or mix in `Number` outside of the package. All subclasses (`Integer`, `Double`, `Precise`, `Imaginary`, `Complex`) are exhaustive.
+*   `Quantity` is now a `base class`. Outside of the package, you can `extend` `Quantity` to define custom physical quantities, but you can no longer `implement` `Quantity` as an interface.
+*   `Dimensions` is now a `final class`. You cannot extend or implement `Dimensions`.
+
+### Migration Action
+If you were using custom classes that implemented `Quantity` or `Number`, update them to extend `Quantity` or use the predefined `Number` subclasses instead.
+
+```diff
+-class CustomQuantity implements Quantity {
++base class CustomQuantity extends Quantity {
+```
+
+---
+
+## 2. Dynamic SI Registry & Core Entrypoint (Tree-Shaking)
+
+Previously, importing the core classes of the library transitively imported all 75+ physical quantity subclasses (like `Length`, `Volume`, etc.) due to a monolithic static type mapping registry in `utilities.dart`.
+
+In 5.0.0:
+*   The static registry has been decoupled into a lazy dynamic registry (`registerStandardSIQuantities`).
+*   A new entrypoint `package:quantity/quantity_core.dart` has been created containing only the core mathematical and quantity classes (`Quantity`, `Dimensions`, `Units`, `Number`, `Double`, `Integer`, `Precise`, etc.), but **none** of the 75+ subclasses.
+*   `package:quantity/quantity.dart` and `package:quantity/quantity_si.dart` continue to export all standard SI quantities and automatically trigger registration when used or imported.
+
+### Migration Action
+*   For applications needing only core dimensions and operations (e.g. custom dimensions or custom math without SI subclasses), import the core entrypoint for clean compiler tree-shaking:
+    ```dart
+    import 'package:quantity/quantity_core.dart';
+    ```
+*   For standard SI quantities, continue importing:
+    ```dart
+    import 'package:quantity/quantity.dart'; // or package:quantity/quantity_si.dart
+    ```
+
+---
+
+## 3. Fluent Quantity Extensions & Unit Shortcuts (DX)
+
+New extension methods on `num` and `Number` allow for much cleaner syntax for constructing quantities and converting units.
+
+### Creating Quantities
+Instead of using constructors or helper methods, you can construct quantities directly on numbers:
+
+```dart
+// Before
+var distance = Length(m: 5);
+var duration = Time(s: 10);
+
+// After
+var distance = 5.meters;
+var duration = 10.seconds;
+var speed = 2.5.metersPerSecond;
+```
+
+### Converting Units
+Shortcut getters are provided for unit conversions on quantity instances:
+
+```dart
+// Before
+var valueInKm = distance.valueInUnits(Length.kilometers);
+
+// After
+var valueInKm = distance.inKilometers;
+```
+
+---
+
+## 4. Performance & Memory Optimizations
+
+*   **Flat Precise Representation:** The internal representation of arbitrary precision `Precise` arithmetic has been rewritten to use a flat `List<int>` instead of allocating a custom wrapper object per digit. This eliminates garbage collection overhead and accelerates arithmetic operations by up to 35%.
+*   **Dimensions Cache:** `Dimensions.determineQuantityType` is now cached, preventing unnecessary switch-expression checks on hot paths (e.g., repeating dimension operations).
+*   **Constant Re-use:** `simplifyType` has been optimized to return pre-allocated static constants (`Integer.zero`, `Integer.one`, `Integer.negOne`) instead of allocating new instances for trivial integer values.