from-iterable/index.js

"use strict";

const { validateArguments } = require("@validatem/core");
const required = require("@validatem/required");
const ValidationError = require("@validatem/error");

const EndOfStream = require("@promistream/end-of-stream");
const simpleSource = require("@promistream/simple-source");

module.exports = function createStreamFromIterable(iterable) {
	validateArguments(arguments, [
		[ "iterable", required, (iterable) => {
			// FIXME: Move to @validatem/ package
			if (!(typeof iterable[Symbol.iterator] === "function")) {
				throw new ValidationError("Must be an iterable (eg. an array)");
			}
		} ]
	]);

	let iterator = iterable[Symbol.iterator]();

	return simpleSource(() => {
		let { done, value } = iterator.next();
		
		if (done) {
			throw new EndOfStream("End of iterable reached");
		} else {
			return value;
		}
	});
};