vue hello world项目
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'use strict';
// https://github.com/tc39/proposal-iterator-helpers
// https://github.com/tc39/proposal-array-from-async
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 getMethod = require('../internals/get-method');
var MAX_SAFE_INTEGER = 0x1FFFFFFFFFFFFF;
var TypeError = global.TypeError;
var createMethod = function (TYPE) {
var IS_TO_ARRAY = TYPE == 0;
var IS_FOR_EACH = TYPE == 1;
var IS_EVERY = TYPE == 2;
var IS_SOME = TYPE == 3;
return function (iterator, fn, target) {
anObject(iterator);
var Promise = getBuiltIn('Promise');
var next = aCallable(iterator.next);
var index = 0;
var MAPPING = fn !== undefined;
if (MAPPING || !IS_TO_ARRAY) aCallable(fn);
return new Promise(function (resolve, reject) {
var closeIteration = function (method, argument) {
try {
var returnMethod = getMethod(iterator, 'return');
if (returnMethod) {
return Promise.resolve(call(returnMethod, iterator)).then(function () {
method(argument);
}, function (error) {
reject(error);
});
}
} catch (error2) {
return reject(error2);
} method(argument);
};
var onError = function (error) {
closeIteration(reject, error);
};
var loop = function () {
try {
if (IS_TO_ARRAY && (index > MAX_SAFE_INTEGER) && MAPPING) {
throw TypeError('The allowed number of iterations has been exceeded');
}
Promise.resolve(anObject(call(next, iterator))).then(function (step) {
try {
if (anObject(step).done) {
if (IS_TO_ARRAY) {
target.length = index;
resolve(target);
} else resolve(IS_SOME ? false : IS_EVERY || undefined);
} else {
var value = step.value;
if (MAPPING) {
Promise.resolve(IS_TO_ARRAY ? fn(value, index) : fn(value)).then(function (result) {
if (IS_FOR_EACH) {
loop();
} else if (IS_EVERY) {
result ? loop() : closeIteration(resolve, false);
} else if (IS_TO_ARRAY) {
target[index++] = result;
loop();
} else {
result ? closeIteration(resolve, IS_SOME || value) : loop();
}
}, onError);
} else {
target[index++] = value;
loop();
}
}
} catch (error) { onError(error); }
}, onError);
} catch (error2) { onError(error2); }
};
loop();
});
};
};
module.exports = {
toArray: createMethod(0),
forEach: createMethod(1),
every: createMethod(2),
some: createMethod(3),
find: createMethod(4)
};