dims

This will allow for storing values like distance or mass, as well as preventing adding grams to feet.

The intent is for these values to be kept in-memory as Mass or Length, without having to worry about the unit except for creation of the value, and when accessing it (for display, storage, etc).

IMPORTANT

This is still a Work-In-Progress. Expect rough-edges, but I am working to smooth them out.

Usage

If you just want to use the pre-generated units (Work in progress: creating more):

// Be sure you include prelude; this exposes required traits
use dims::prelude::*;
use dims::us::*;
use dims::si::*;

let feet = FOOT.from(12.5);
let mm = MILLIMETRE.from(317.5);
assert_eq!(feet, mm);
// You can add between different systems
// They are all stored as `metre` here, anyway
let another = feet + mm;
// You can also multiply to get area (and on further to get volume)
let area = feet * mm;
assert_eq!(area, SQFT.from(156.25));
let mass = GRAM.from(18.25);
// You can also create them the other way around
let this_works = Measure::new(&INCH,0.125);
// You can grab the stored value as a float via
let raw = mm.val_as(&INCH);
// The compiler will not allow you to add between systems:
// let nope = mass + area; // <== Compiler throws an error

Base Structs and Traits

• MeasureSystem: A system of measurement (EX: Length, Mass, Volume) used to prevent cross-over between a Measure. These are implemented in dims
• Measure: The actual value stored stored. Any value created (like inches or pounds) will be converted to the base unit (EX: Metre for Length, Gram for Mass).
• UnitTrait: A trait used to create a type of unit. This allows for creation of a custom conversion function between units. For nearly all situations, UnitSimple can be used.
• UnitSimple: A basic implementation of UnitTrait. The ratio between the specified unit and the base unit are specified, as well as the offset.
• UnitFormat: A bit more complex implementation of UnitTrait. The ratio between the specified unit and the base unit are specified, as well as the offset. In addition, the textual name for the unit is stored.

dims

This contains a set of pre-made systems and units. These will be added to as time goes on.

The current systems are:

*Notes on Temperature:

• No checking for negative values is performed, as endothermic reactions would have a negative value when applied to the environment.
• The debug unit for this is Celcius

Other Notes

Performance

There is no measurable impact on release performance compared to the stored value (from what my very basic tests can show). The Measure struct is [repr(transparent)], so everything but the value itself is optimized away. Debug mode code does have a hit to performance, however.

Crate options for dims

• f64 is available as an option; f32 is the default. Other datatypes can be specified when using custom units (see dims_core)
• std is the default option, and defaults to using the standard library.
  This enables the UnitFormatTrait (as the functions return String), but no_std can still be used with str (see below) to store the unit name info.
• str (default) will utilize UnitFormat and store:
  • abbr: Abbreviated unit name (m or ft)
  • singular: Singular name of a unit (metre or foot)
  • plural: Plural name of the unit (metres or feet)
• si provides SI/Metric units (on by default)
• us provides US (or 'Merican) units (on by default)
• debug_us will use units as specified in the table above for debugging.

IMPORTANT

Selecting us or debug_us in the above options will NOT change the base unit. It will still be stored in SI.