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import isArrayLike from './internal/isArrayLike.js'
import breakLoop from './internal/breakLoop.js'
import eachOfLimit from './eachOfLimit.js'
import once from './internal/once.js'
import onlyOnce from './internal/onlyOnce.js'
import wrapAsync from './internal/wrapAsync.js'
import awaitify from './internal/awaitify.js'
// eachOf implementation optimized for array-likes
function eachOfArrayLike(coll, iteratee, callback) {
callback = once(callback);
var index = 0,
completed = 0,
{length} = coll,
canceled = false;
if (length === 0) {
callback(null);
}
function iteratorCallback(err, value) {
if (err === false) {
canceled = true
}
if (canceled === true) return
if (err) {
callback(err);
} else if ((++completed === length) || value === breakLoop) {
callback(null);
}
}
for (; index < length; index++) {
iteratee(coll[index], index, onlyOnce(iteratorCallback));
}
}
// a generic version of eachOf which can handle array, object, and iterator cases.
function eachOfGeneric (coll, iteratee, callback) {
return eachOfLimit(coll, Infinity, iteratee, callback);
}
/**
* Like [`each`]{@link module:Collections.each}, except that it passes the key (or index) as the second argument
* to the iteratee.
*
* @name eachOf
* @static
* @memberOf module:Collections
* @method
* @alias forEachOf
* @category Collection
* @see [async.each]{@link module:Collections.each}
* @param {Array|Iterable|AsyncIterable|Object} coll - A collection to iterate over.
* @param {AsyncFunction} iteratee - A function to apply to each
* item in `coll`.
* The `key` is the item's key, or index in the case of an array.
* Invoked with (item, key, callback).
* @param {Function} [callback] - A callback which is called when all
* `iteratee` functions have finished, or an error occurs. Invoked with (err).
* @returns {Promise} a promise, if a callback is omitted
* @example
*
* // dev.json is a file containing a valid json object config for dev environment
* // dev.json is a file containing a valid json object config for test environment
* // prod.json is a file containing a valid json object config for prod environment
* // invalid.json is a file with a malformed json object
*
* let configs = {}; //global variable
* let validConfigFileMap = {dev: 'dev.json', test: 'test.json', prod: 'prod.json'};
* let invalidConfigFileMap = {dev: 'dev.json', test: 'test.json', invalid: 'invalid.json'};
*
* // asynchronous function that reads a json file and parses the contents as json object
* function parseFile(file, key, callback) {
* fs.readFile(file, "utf8", function(err, data) {
* if (err) return calback(err);
* try {
* configs[key] = JSON.parse(data);
* } catch (e) {
* return callback(e);
* }
* callback();
* });
* }
*
* // Using callbacks
* async.forEachOf(validConfigFileMap, parseFile, function (err) {
* if (err) {
* console.error(err);
* } else {
* console.log(configs);
* // configs is now a map of JSON data, e.g.
* // { dev: //parsed dev.json, test: //parsed test.json, prod: //parsed prod.json}
* }
* });
*
* //Error handing
* async.forEachOf(invalidConfigFileMap, parseFile, function (err) {
* if (err) {
* console.error(err);
* // JSON parse error exception
* } else {
* console.log(configs);
* }
* });
*
* // Using Promises
* async.forEachOf(validConfigFileMap, parseFile)
* .then( () => {
* console.log(configs);
* // configs is now a map of JSON data, e.g.
* // { dev: //parsed dev.json, test: //parsed test.json, prod: //parsed prod.json}
* }).catch( err => {
* console.error(err);
* });
*
* //Error handing
* async.forEachOf(invalidConfigFileMap, parseFile)
* .then( () => {
* console.log(configs);
* }).catch( err => {
* console.error(err);
* // JSON parse error exception
* });
*
* // Using async/await
* async () => {
* try {
* let result = await async.forEachOf(validConfigFileMap, parseFile);
* console.log(configs);
* // configs is now a map of JSON data, e.g.
* // { dev: //parsed dev.json, test: //parsed test.json, prod: //parsed prod.json}
* }
* catch (err) {
* console.log(err);
* }
* }
*
* //Error handing
* async () => {
* try {
* let result = await async.forEachOf(invalidConfigFileMap, parseFile);
* console.log(configs);
* }
* catch (err) {
* console.log(err);
* // JSON parse error exception
* }
* }
*
*/
function eachOf(coll, iteratee, callback) {
var eachOfImplementation = isArrayLike(coll) ? eachOfArrayLike : eachOfGeneric;
return eachOfImplementation(coll, wrapAsync(iteratee), callback);
}
export default awaitify(eachOf, 3)
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