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6945 :: Can I use async/await to work with JS Promises?

• akavel (orginal) [2020-10-17T20:07:54+02:00] view original

  I'm in progress of writing a Firefox Webextension with Nim, using Karax for rendering. I got stuck in a place where:

  1. I'm writing a proc used in Karax callback (onclick)
  2. I need to access an async Webextension API (returning a JS `Promise) <https://developer.mozilla.org/en-US/docs/Mozilla/Add-ons/WebExtensions/API/bookmarks/create>`_, and I need to do it multiple times in sequence.

  My question is: can I do (2.) in some simpler way than a sequence of .then(proc...).then(proc...).then(proc...) callbacks? I found the asyncjs package, but I'm not sure if I can plug it somehow in my situation. The Webext API returns a JS Promise, and I'm assuming Karax callbacks cannot be async procs. I don't know JS enough to understand what I can do now, if anything at all.

  Can someone possibly help me? TIA!

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• vijaymarupudi (orginal) [2020-10-17T20:20:38+02:00] view original

  Something like this should work

  import asyncjs
  
  
  proc main() {.async.} =
    let x = await apiFunction()
  
  
  main()
  Run

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• akavel (orginal) [2020-10-19T02:23:59+02:00] view original

  Thanks! I also found out that async by itself basically makes a function wrap its returned result in a Promise - so I can just pass an async function into .then() and it works; and also that I can use importcpp to await the WebExt API functions.

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