Unity version 0.7.0

v0.7.0 (2026-05-10)

Enhancements

• Added gb as an alias for gigabyte so it doesn't collide with GNU's gilbert after Unity.GnuUnitsImporter.import/0.

• Conversion errors now include each side's base-unit decomposition (e.g., "gilbert" reduces to "ampere") so dimensional mismatches are obvious.

Unity version 0.5.0

v0.5.0 (2026-04-13)

Enhancements

• Added 20 new math functions: hyperbolic trig (sinh, cosh, tanh, asinh, acosh, atanh), two-argument functions (atan2, hypot, gcd, lcm, min, max, mod), and factorial/gamma.

• Hex (0xFF), octal (0o77), and binary (0b1010) number literals. Underscore digit separators (1_000_000, 0xFF_FF) in all number formats.

• Tab completion for unit names, function names, REPL commands, and custom unit names.

• Date/time arithmetic: now(), today(), datetime("2025-01-01T00:00:00Z"), unixtime(n), timestamp(dt). DateTime subtraction yields duration; DateTime ± duration yields DateTime.

• String literal support in expressions ("...") for function arguments.

• Zero-argument function calls (now(), today()).

• assert_eq(a, b) and assert_eq(a, b, tolerance) for verifying unit equivalences with automatic conversion and optional tolerance.

• Introspection functions: unit_of(expr), value_of(expr), is_dimensionless(expr).

• Percentage functions: increase_by(val, pct), decrease_by(val, pct), percentage_change(from, to). Work on both plain numbers and units.

• Variables with trailing digits (e.g., t1) now resolve correctly from the environment before falling back to concatenated-exponent parsing.

Unity version 0.4.0

v0.4.0 (2026-04-13)

Enhancements

• Added 75 nonlinear (:special) conversion functions covering temperature scales (tempc, tempf, tempreaumur), decibel/logarithmic scales (decibel, dBm, dBW, dBV, dBSPL, neper, bel, musicalcent, bril), density hydrometers (baume, twaddell, quevenne, pH, apidegree), wire/screw/shotgun gauges, shoe and ring sizes, photographic exposure (EV100, APEX values), atmospheric models, astronomical magnitudes, gauge pressure, and geometry/network helpers.

• Special conversions work both as function calls (tempc(100) → 373.15 kelvin) and as unit conversions (100 tempc to fahrenheit → 212 fahrenheit).

• Refactored Beaufort scale from hardcoded logic to the general :special conversion mechanism.

• Total GNU Units coverage: ~2,440 linear units + 250 constants + 75 special conversions = ~2,760 used.

Unity version 0.3.0

v0.3.0 (2026-04-13)

Bug Fixes

• Batch load custom units to avoid :persistent_term churn.

Unity version 0.2.0

v0.2.0 (2026-04-13)

Bug Fixes

• REPL now has full line editing and history when started via mix run -e "Unity.Repl.start()". Bootstraps the Erlang terminal driver via shell:start_interactive/1 when not running under IEx. History is persisted to ~/.unity_history/.

Enhancements

• GNU Units importer now imports ~2,460 custom units (was ~1,700) and extracts ~250 dimensionless constants as let bindings.

• Added support for all CLDR unit categories including mass-density, voltage, electric-charge, illuminance, radioactivity, and other derived SI quantities.

• Added derived category mappings for compound SI quantities not in CLDR (specific-heat, volume-flow-rate, areal-density, thermal-conductivity, dynamic-viscosity, etc.).

• CLDR compound base unit strings now use correct component ordering (kilogram, meter, second, ampere, kelvin, ...) matching the CLDR base_unit_to_quantity keys.

• Added bindings REPL command to display current variable bindings.

• import/1 now returns a :constants map of dimensionless values suitable for use as evaluation environment bindings.

Unity version 0.1.0

v0.1.0 (2026-04-11)

Initial release.

Features

• NimbleParsec-based expression parser supporting integers, floats, rational numbers (1|3), unit names, arithmetic (+, -, *, /, ^, **), per, conversion (to, in, ->), parentheses, function calls, concatenated exponents (cm3), and juxtaposition multiplication (kg m).

• AST interpreter evaluating expressions against Localize.Unit and Localize.Unit.Math.

• Over 150 unit aliases mapping common abbreviations (m, km, ft, lb, mph, etc.) to CLDR unit identifiers, with fuzzy suggestions for unknown units via String.jaro_distance/2.

• Built-in functions: sqrt, cbrt, abs, round, ceil, floor, sin, cos, tan, asin, acos, atan, ln, log, log2, exp.

• Measurement system conversion targets: to metric, to us, to uk, to imperial, to SI, to preferred. The preferred keyword selects the measurement system appropriate for the current locale's territory.

• Variable bindings via let name = expression with subsequent reference by name.

• _ (underscore) references the previous REPL result for chained conversions.

• Mixed-unit decomposition: 3.756 hours to h;min;s → 3 hours, 45 minutes, 21.6 seconds.

• Locale-aware output via Localize.Unit.to_string/2 and Localize.Number.to_string/2. REPL locale command and CLI --locale flag for runtime locale switching.

• Interactive REPL with help, list, search, conformable, info, and locale commands. Command history persisted to ~/.units_history.

• CLI entry point supporting single-expression evaluation, two-argument GNU-style conversion, verbose (-v), terse (-t), exponential (-e), digits (-d), output-format (-o), strict (-s), and one-line (-1) modes, stdin piping, --conformable, and --list.

• Reciprocal conversion line shown by default for conversions (suppressed with --strict or --one-line).

• Formatter with default, verbose, and terse output modes.

• User-friendly error messages with parse position indicators and fuzzy unit suggestions.