add some more units to the export surface

Author: phlptp

README.md

@@ -201,6 +201,16 @@ int main()
 }
 ```
 
+The module currently guarantees a curated public surface in the `units::` namespace, including:
+
+- Core types and functions such as `unit`, `precise_unit`, `measurement`, `precise_measurement`, `convert`, `quick_convert`, `unit_from_string`, `measurement_from_string`, and `to_string`
+- All seven SI base units by symbol or common name: `m`/`meter`, `kg`/`kilogram`, `s`/`second`, `A`/`Ampere`, `K`/`Kelvin`, `mol`, and `cd`
+- Common SI and SI-derived units: `rad`, `Hz`, `N`, `J`, `W`, `V`, `ohm`, `Pa`, `C`, `cm`, `mm`, `km`, `L`, `g`, `degC`, and `degF`
+- Common non-SI and scalar units: `minute`, `h`, `hr`, `ft`/`foot`, `in`/`inch`, `mile`, `lb`, `gal`, `deg`, `mph`, `count`, and `currency`
+- Main prefixes as scalar units: `milli`, `micro`, `nano`, `pico`, `kilo`, `mega`, and `giga`
+
+Additional units remain available through the traditional headers, especially in `units::precise` and its subnamespaces.
+
 ## Try it out
 
 If you want to try out the string conversion components. There is server running that can do the string conversions

units/units.cppm

@@ -51,27 +51,55 @@ using ::units::unit_from_string;
 using ::units::operator*;
 using ::units::operator/;
 
+using ::units::Ampere;
 using ::units::A;
+using ::units::bar;
 using ::units::C;
+using ::units::cd;
 using ::units::cm;
+using ::units::currency;
+using ::units::count;
+using ::units::deg;
+using ::units::degC;
+using ::units::degF;
 using ::units::ft;
+using ::units::foot;
 using ::units::g;
+using ::units::gal;
+using ::units::giga;
 using ::units::h;
 using ::units::hr;
 using ::units::Hz;
+using ::units::in;
+using ::units::inch;
 using ::units::J;
 using ::units::K;
+using ::units::Kelvin;
 using ::units::kg;
+using ::units::kilogram;
+using ::units::kilo;
 using ::units::km;
 using ::units::L;
 using ::units::m;
+using ::units::meter;
+using ::units::mega;
+using ::units::mile;
+using ::units::micro;
+using ::units::milli;
 using ::units::mm;
 using ::units::mol;
+using ::units::minute;
 using ::units::N;
+using ::units::nano;
+using ::units::Pa;
 using ::units::ohm;
 using ::units::one;
+using ::units::pico;
 using ::units::rad;
 using ::units::s;
+using ::units::second;
+using ::units::lb;
+using ::units::mph;
 using ::units::V;
 using ::units::W;
 }  // namespace units