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Logical nullish/or (and other types of) assignment(s) doesn't work in Svelte

See original GitHub issue

Describe the bug

Logical nullish assignment (as well as Logical OR assignment and other types of Logical assignments) doesn’t work in Svelte

Reproduction

https://svelte.dev/repl/e5054000ffb442ad85c4d7bbc821d8f5?version=3.42.1

Logs

unexpected token '??='
SyntaxError: Unexpected token '??='
    at new Function (<anonymous>)
    at instantiateModule (/mnt/sda1/Programovanie/test/node_modules/vite/dist/node/chunks/dep-c1a9de64.js:73464:9)

System Info

System:
    OS: Linux 5.11 Ubuntu 20.04.2 LTS (Focal Fossa)
    CPU: (8) x64 Intel(R) Core(TM) i5-8300H CPU @ 2.30GHz
    Memory: 216.20 MB / 15.46 GB
    Container: Yes
    Shell: 5.0.17 - /bin/bash
  Browsers:
    Chrome: 92.0.4515.131
    Firefox: 91.0

Severity

annoyance

Issue Analytics

State:
Created 2 years ago
Comments:16 (16 by maintainers)

Top GitHub Comments

3reactions

bluwycommented, Aug 14, 2021

I don’t think this is related to svelte-preprocess nor svelte-repl. Svelte should be able to parse logical assignments, and also track reactivity through it. Currently the former should only require an update to acorn, the latter however may need some changes to make sure it works.

1reaction

Conduitrycommented, Aug 14, 2021

Oh, right, I had thought this was already working in Svelte. What you’re seeing in the REPL is just that its version of Rollup needs upgrading to support that syntax. There may be a PR for that already. In any case, this works in Svelte itself, and if you’re having issues with something unrelated, please pursue the usual avenues for support.