vue hello world项目
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'use strict';
// https://github.com/tc39/proposal-iterator-helpers
var $ = require('../internals/export');
var global = require('../internals/global');
var call = require('../internals/function-call');
var aCallable = require('../internals/a-callable');
var anObject = require('../internals/an-object');
var getBuiltIn = require('../internals/get-built-in');
var Promise = getBuiltIn('Promise');
var TypeError = global.TypeError;
$({ target: 'AsyncIterator', proto: true, real: true, forced: true }, {
reduce: function reduce(reducer /* , initialValue */) {
var iterator = anObject(this);
var next = aCallable(iterator.next);
var noInitial = arguments.length < 2;
var accumulator = noInitial ? undefined : arguments[1];
aCallable(reducer);
return new Promise(function (resolve, reject) {
var loop = function () {
try {
Promise.resolve(anObject(call(next, iterator))).then(function (step) {
try {
if (anObject(step).done) {
noInitial ? reject(TypeError('Reduce of empty iterator with no initial value')) : resolve(accumulator);
} else {
var value = step.value;
if (noInitial) {
noInitial = false;
accumulator = value;
loop();
} else {
Promise.resolve(reducer(accumulator, value)).then(function (result) {
accumulator = result;
loop();
}, reject);
}
}
} catch (err) { reject(err); }
}, reject);
} catch (error) { reject(error); }
};
loop();
});
}
});