axax/esnext/scan.js

A library of async iterator extensions for JavaScript including ```map```, ```reduce```, ```filter```, ```flatMap```, ```pipe``` and [more](https://github.com/jamiemccrindle/axax/blob/master/docs/API.md#functions).

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
/**
 * Goes through a iterable applying the scanner function to the accumulator
 * returning the accumulator at each step
 */
function scan(scanner, init) {
    return async function* inner(source) {
        let accumulator = await init;
        for await (const next of source) {
            yield accumulator;
            accumulator = await scanner(accumulator, next);
        }
        yield accumulator;
    };
}
exports.scan = scan;