2021-03-26
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#vanilla javascript
Linda Ikechukwu
39897
Mar 26, 2021 ⋅ 4 min read

New ES2021 features you may have missed

Linda Ikechukwu Frontend developer. Writer. Community Strategist. Building web interfaces that connect products to their target users.

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3 Replies to "New ES2021 features you may have missed"

  1. Hi, thanks for writing this good article, I love it.

    However I want to propose a correction for Promise.all in Promise.any part, The Promise.all should be reject if any of the promise rejected and resolve if all promise resolved.

    https://developer.mozilla.org/en-
    US/docs/Web/JavaScript/Reference/Global_Objects/Promise/all

    Keep writing good stuff.

  2. “`
    const promise1 = new Promise((resolve) => setTimeout((resolve) => resolve, 300, ‘faster’);
    const promise2 = new Promise((reject) => setTimeout( (reject) =>reject, 100,”fastest”)
    const promise3 = new Promise((resolve) => setTimeout( (resolve) => resolve,700,’fast’);
    “`

    This promise code is just completely wrong, even if you fix the missing closing brackets. Your `setTimeout` calls take a `resolve => resolve` callback, but this reject is not the one from the promise, it’s an internal parameter of the callback. You might as well have passed the callback `foo => foo` , and it will have the same result.

    `promise2` even renames the “resolve” parameter as `reject`. Further adding to the wrongness.

    I believe you meant:

    “`
    const promise2 = new Promise((_, reject) => setTimeout(reject, 100,”fastest”));
    “`

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