Fixed Size Array
Based on this comment
import {FixedSizeArray} from 'funny-types/fixed-array-size'
const goodArray: FixedSizeArray<number, 2> = [1, 2]
And you'll have type error if:
import {FixedSizeArray} from 'funny-types/fixed-array-size'
const array: FixedSizeArray<number, 2> = [1, 2, 3]
or
import {FixedSizeArray} from 'funny-types/fixed-array-size'
const array: FixedSizeArray<number, 2> = [1, 2]
array[2] = 5