PositiveInteger

Integer value object constrained to non-negative values.

Import

import { PositiveInteger } from '@haskou/value-objects';

Signature

class PositiveInteger extends PositiveNumber

Constructor

constructor(value: number | NumberValueObject)

Validation

Accepts integers greater than or equal to 0.

Throws

This class can throw:

• InvalidPositiveNumberError
• InvalidIntegerError
• InvalidNumberError

Example

import { PositiveInteger } from '@haskou/value-objects';

const zero = new PositiveInteger(0);
const items = new PositiveInteger(3);

items.subtract(1).valueOf(); // 2
items.subtract(4); // throws InvalidPositiveNumberError
items.divide(2); // throws InvalidIntegerError

Notes

• Like PositiveNumber, it accepts 0. It is not an Integer subclass: instanceof Integer is false.
• The sign is checked first, so -0.5 throws InvalidPositiveNumberError, not InvalidIntegerError.
• Arithmetic is inherited from NumberValueObject and goes through the constructor, so a result that is negative or not an integer throws.

Related

• Integer
• PositiveNumber
• Reference overview