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FlowTyped Declarations

See original GitHub issue

In usage with Flow, I get errors like this:

screen shot 2018-01-09 at 12 14 30 am

I am wondering that, since the values passed into condition are negated to truthy or falsey, shouldn’t it accept any type?

Apologies if this question belongs elsewhere. If so, please do direct me.

Issue Analytics

  • State:open
  • Created 6 years ago
  • Reactions:1
  • Comments:5 (1 by maintainers)

github_iconTop GitHub Comments

JalilArfaouicommented, Apr 4, 2018

Hello @AlexGilleran

I agree it is a matter of opinion if we should or not have an explicit boolean cast in conditions.

Except that I think, like @colshacol, that we should have a consistent behavior between if (foo) and <If condition={foo}>.

So, since Flow does not raise an error on if statement with non-boolean value, I think this link should not either.

draperunnercommented, Jun 15, 2018

I agree @colshacol and @JalilArfaoui . Since it is so obvious that whatever passed into <If condition={}> will be treated as a boolean, like a normal if statement in JavaScript, I think it should be typed as any.

In my project we end up casting all statements with Boolean() like this: <If condition={Boolean(...)}>, which I think is just noisy.

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