#si-units #units #measurement #physics #unit #no-alloc

macro no-std simple-si-units-macros

This is the procedural macro library for crate simple-si-units

24 releases (2 stable)

1.0.1 Apr 28, 2023
0.9.0 Apr 25, 2023
0.7.4 Mar 23, 2023
0.3.1 Nov 7, 2022

#16 in #si-units

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Used in simple-si-units

MPL-2.0 license

460 lines


This crate exists to support the simple-si-units. Please go there for more information.


Crate simple-si-units-macros exports the following derive macros:


This macro uses the NumLike trait from simple-si-units-core to derive all of the relevant mathematical operators for the derived struct, so long as that struct contains only a single named field. For example:

use simple_si_units_macros::UnitStruct;
use simple_si_units_core::NumLike;

#[derive(UnitStruct, Debug, Clone)]
struct HyperVelocity<T: NumLike>{
  square_meters_per_second: T

fn weighted_hypervel_sum<T: NumLike>(a: HyperVelocity<T>, b: HyperVelocity<T>, weight: f64) -> HyperVelocity<T>
  where T:NumLike + From<f64>
  return weight*a + (1.-weight)*b;


This library is open source, licensed under the Mozilla Public License version 2.0. In summary, you may include this source code as-is in both open-source and proprietary projects without requesting permission from me, but if you modify the source code from this library then you must make your modified version of this library available under an open-source license.


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