no lodash

nodash.js

// follow python range func.
function range(start, end = null, step = 1) {
    if (end === null) return Array(start).fill().map((_, index) => index)

    const result = []
    for (let i = start; step > 0 ? i < end : i > end; i += step || 1) {
        result.push(i)
    }
    return result
}