axax/esnext/toCallbacks.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 });
/** Provides a way for callbacks to signal early completion */
class StopError extends Error {
}
exports.StopError = StopError;
/**
 * Converts an async iterable into a series of callbacks. The function returns
 * a promise that resolves when the stream is done
 *
 * @param callback the callback that gets called for each value
 */
function toCallbacks(callback) {
    return async function inner(source) {
        const iterator = source[Symbol.asyncIterator]();
        while (true) {
            const result = await iterator.next();
            try {
                await callback(result);
            }
            catch (StopError) {
                return;
            }
            if (result.done) {
                return;
            }
        }
    };
}
exports.toCallbacks = toCallbacks;