---
title: "Discussion on \"Creating a JavaScript promise from scratch, part 7: Unhandled promise rejections\" | Hashnode"
description: "Discussion on \"Creating a JavaScript promise from scratch, part 7: Unhandled promise rejections\". This post originally appeared on the Human Who Codes blog on January 19, 2021.\nWhen promises were introduced in ECMAScript 2015, they had an interesting flaw: if a promise didn't have a rejection handler and was later rejected, you would have no idea..."
url: "https://hashnode.com/posts/creating-a-javascript-promise-from-scratch-part-7-unhandled-promise-rejections/6025bff3c6d91052dafe9156"
---

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# [Creating a JavaScript promise from scratch, part 7: Unhandled promise rejections](https://hashnode.humanwhocodes.com/creating-a-javascript-promise-from-scratch-part-7-unhandled-promise-rejections?utm_source=hashnode&utm_medium=feed)

This post originally appeared on the Human Who Codes blog on January 19, 2021. When promises were introduced in ECMAScript 2015, they had an interesting flaw: if a promise didn't have a rejection handler and was later rejected, you would have no idea...

Jan 19, 2021 · 29 min read · hashnode.humanwhocodes.com  
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-   [#promises](https://hashnode.com/tag/promises)

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