Fibonacci sequence implemented in 6 different ways with JavaScript. A nice excuse to explore functions, iterators, generators, iterable values, event emitters and streams!
As usual, npm-it-away:
npm i --save fib-itThe library exposes 6 different implementations of the fibonacci sequence.
The sequence will be infinite (as much as it can be considering JavaScript integer space) unless limited to max number.
const { genFib } = require('fib-it')
const f = genFib(6) // limit the sequence to numbers below 6
f() // 1
f() // 1
f() // 2
f() // 3
f() // 5
f() // null
f() // nullconst { genFibIterator } = require('fib-it')
it = genFibIterator(6) // { next: [Function: next] }
it.next() // { value: 1, done: false }
it.next() // { value: 1, done: false }
it.next() // { value: 2, done: false }
it.next() // { value: 3, done: false }
it.next() // { value: 5, done: false }
it.next() // { value: null, done: true }
// or
it = genFibIterator(6)
let result = it.next()
while (!result.done) {
console.log(result.value)
result = it.next()
}
// 1
// 1
// 2
// 3
// 5gen = fibGenerator(6) // {}
gen.next() // { value: 1, done: false }
gen.next() // { value: 1, done: false }
gen.next() // { value: 2, done: false }
gen.next() // { value: 3, done: false }
gen.next() // { value: 5, done: false }
gen.next() // { value: null, done: true }
gen.next() // { value: undefined, done: true }
// or
gen = fibGenerator(6)
[...gen] // [ 1, 1, 2, 3, 5 ]const { genFibIterable } = require('fib-it')
it = genFibIterable(6) // { [Symbol(Symbol.iterator)]: [GeneratorFunction: [Symbol.iterator]] }
[...it] // [ 1, 1, 2, 3, 5 ]
// or
for (n of f) { console.log(n) }
// 1
// 1
// 2
// 3
// 5const { FibEmitter } = require('fib-it')
const fe = new FibEmitter(6, 10)
fe.on('data', n => console.log(n))
fe.on('end', () => console.log('done!'))
fe.start()
// 1
// 1
// 2
// 3
// 5
// done!const s = new FibStream(7) // FibStream { ... }
s.on('data', chunk => console.log(chunk.readUInt32LE(0).toString()))
s.on('end', () => console.log('done!'))
// 1
// 1
// 2
// 3
// 5
// done!There are some actual use cases for the fibonacci sequence. So maybe you need something like this in your code!
In reality this is just an experiment to compare different methodology to generate data sequences in JavaScript, so I expect it to be used mostly for education purposes rather than for production code.
Also with this goal in mind, the code is kept relatively simple and it's not meant to be feature-complete or error-proof.
Feel more than welcome to report bugs or propose changes.
Licensed under MIT.