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1import type {IntRange} from './int-range';
2import type {Sum} from './sum';
3
4/**
5Generate a union of numbers.
6
7The numbers are created from the given `Start` (inclusive) parameter to the given `End` (inclusive) parameter.
8
9You skip over numbers using the `Step` parameter (defaults to `1`). For example, `IntClosedRange<0, 10, 2>` will create a union of `0 | 2 | 4 | 6 | 8 | 10`.
10
11Note: `Start` or `End` must be non-negative and smaller than `999`.
12
13Use-cases:
141. This can be used to define a set of valid input/output values. for example:
15 ```
16 type Age = IntClosedRange<0, 120>; //=> 0 | 1 | 2 | ... | 119 | 120
17 type FontSize = IntClosedRange<10, 20>; //=> 10 | 11 | ... | 19 | 20
18 type EvenNumber = IntClosedRange<0, 10, 2>; //=> 0 | 2 | 4 | 6 | 8 | 10
19 ```
202. This can be used to define random numbers in a range. For example, `type RandomNumber = IntClosedRange<0, 100>;`
21
22@example
23```
24import type {IntClosedRange} from 'type-fest';
25
26// Create union type `0 | 1 | ... | 9`
27type ZeroToNine = IntClosedRange<0, 9>;
28
29// Create union type `100 | 200 | 300 | ... | 900`
30type Hundreds = IntClosedRange<100, 900, 100>;
31```
32
33@see IntRange
34*/
35export type IntClosedRange<Start extends number, End extends number, Skip extends number = 1> = IntRange<Start, Sum<End, 1>, Skip>;