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Flow error: Cannot use conditional as a computed property

See original GitHub issue

I’m seeing these errors, using Flow 0.123.0. Also seeing them on the version of flow used by this repo if I paste the code into try flow.

Error ┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ node_modules/react-window/src/createGridComponent.js:615:12

Cannot use conditional [1] as a computed property. Computed properties may only be primitive literal values, but
conditional [1] is a union. Can you add a literal type annotation to conditional [1]? See
https://flow.org/en/docs/types/literals/ for more information on literal types.

     612│       } else {
     613│         itemStyleCache[key] = style = {
     614│           position: 'absolute',
 [1] 615│           [direction === 'rtl' ? 'right' : 'left']: getColumnOffset(
     616│             this.props,
     617│             columnIndex,
     618│             this._instanceProps


Error ┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈┈ node_modules/react-window/src/createListComponent.js:471:12

Cannot use conditional [1] as a computed property. Computed properties may only be primitive literal values, but
conditional [1] is a union. Can you add a literal type annotation to conditional [1]? See
https://flow.org/en/docs/types/literals/ for more information on literal types.

     468│
     469│         itemStyleCache[index] = style = {
     470│           position: 'absolute',
 [1] 471│           [direction === 'rtl' ? 'right' : 'left']: isHorizontal ? offset : 0,
     472│           top: !isHorizontal ? offset : 0,
     473│           height: !isHorizontal ? size : '100%',
     474│           width: isHorizontal ? size : '100%',

Issue Analytics

State:
Created 3 years ago
Reactions:1
Comments:8

Top GitHub Comments

2reactions

cstoddartcommented, Aug 10, 2020

@jedwards1211 I had this same error. Finally fixed it this morning by upgrading flow-bin to 0.129.0

So it turns out this was only a temporary solution. I intended to put up a PR with a fix, but when I pulled down the repo I noticed the necessary changes were already there.

@bvaughn Can you make a release with the latest changes?

In the mean time, I can confirm that "react-window": "bvaughn/react-window#master" in my package.json is working well for me. 👍

0reactions

cstoddartcommented, Oct 27, 2020

Definitely not a solution I’m happy to suggest either way. I actually ended up pulling the code I needed from this repo and put it directly into my codebase. Kind of a pain but it’s not a ton of code 🤷‍♂️