wishwash/wishwash.js

Wishwash takes 4 arguments: a value (usually an iterator), a min, a max, and an inclusive qualifier, and counts back and forth between the min and max to your value. Wishwash can be likened to the modulus operator but instead of being used as a single dir

module.exports = (i, min, max, inclusive) => {

//Begin preliminary checks

    if (i === undefined) {
        return `Your iterator is undefined.`
    }

    if (min === undefined) {
        return `Your min is undefined.`
    }

    if (max === undefined) {
        return `Your max is undefined.`
    }

    if (inclusive === undefined) {
        return `Your "inclusive" qualifier is undefined.`
    }

    if (isNaN(i)) {
        return `"${i}" is not a number.`
    }

    if (isNaN(min)) {
        return `"${min}" is not a number.`
    }

    if (isNaN(max)) {
        return `"${max}" is not a number.`
    }

    if (typeof inclusive !== 'boolean') {
        return `Your "inclusive" qualifier must be boolean.`
    }

    if (inclusive === false) { //Beyond 9999999999999999 IEEE 754 Floating Point conversion inaccuracies will occur in JavaScript.
        if (i > 9999999999999998) {
            return `Your iterator is too large to maintain IEEE 754 Floating Point conversion accuracy.`
        }

        if (min > 9999999999999998) {
            return `Your min is too large to maintain IEEE 754 Floating Point conversion accuracy.`
        }

        if (max > 9999999999999998) {
            return `Your max is too large to maintain IEEE 754 Floating Point conversion accuracy.`
        }

    } else {
        if (i > 9999999999999999) {
            return `Your iterator is too large to maintain IEEE 754 Floating Point conversion accuracy.`
        }

        if (min > 9999999999999999) {
            return `Your min is too large to maintain IEEE 754 Floating Point conversion accuracy.`
        }

        if (max > 9999999999999999) {
            return `Your max is too large to maintain IEEE 754 Floating Point conversion accuracy.`
        }
    }

    if (min >= max) {
        return `Your max must be greater than your min.`
    }

//End preliminary checks

    const mini = inclusive ? min : min + 1
    const maxi = inclusive ? max : max - 1

    return maxi - Math.abs(maxi - mini - (i % ((maxi - mini) * 2)))
}