TypeScript Units & Measurement

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A library for handling units and measurements in TypeScript. The library is broken down into several modules, each of which can be used independently.

@adam-rocska/units-and-measurement

The main module providing all the units necessary or convenient for working with units and measurements safely without boilerplate.

Measurements may be expressed as:

• tuples: Simplest form: [15, "px"].
• objects: Simplest form: { value: 15, unit: "px" }.
• strings: Simplest form: "15px". Yes. THAT simple.
• dimension: Simplest form when using a known provided dimension: inches(11).

where dimensions are a special monad of an object representation.

Utilities provided for measurements:

• type predicates: They help identify any value as a general or specific type of measurement.
• factory utilities: called simply measurement, specialized by the respective specifier namespace or used in its general form. Not necessary but useful in many cases to reduce boilerplates.
• value and unit readers: They help extract the value or unit from a measurement, let it be a general or specific type of measurement.
• toFixed and toPrecision: Provide alternatives for the Number type's toFixed and toPrecision methods on both specific and generic measurements.

@adam-rocska/units-and-measurement/operations

A module providing convenient utilities to perform operations on measurements. It includes the following:

• arithmetic operations: addition, subtraction, multiplication, division, exponentiation, root and logarithm.
• comparison operations
• a utility for general purpose arithmetic operations
• a utility for general purpose logical operations

@adam-rocska/units-and-measurement/${DIMENSION}

Every dimension submodule provides the following:

• Unit symbol type predicates
• List of known unit symbols
• Unit symbols as types.
• The dimension object, as anyone would provide one using @adam-rocska/units-and-measurement
• Aliases for the dimension factories.

Example

const paperWidth = inches(5.5);
const paperHeight = inches(11);

// toFixed, to avoid floating point errors
if (areEqual(toFixed(paperWidth.cm, 2), centimeters(13.97))) {
  console.log("The paper width is 13.97 cm.");
}