Document contravariance and covariance

niieani / typescript-vs-flowtype

Differences between Flowtype and TypeScript -- syntax and usability

MIT License

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Open FezVrasta opened 5 years ago

FezVrasta commented 5 years ago

Flow supports contravariance (-), TypeScript doesn't.

Also, TypeScript doesn't support covariance (+) on all its types, but just some of them.

niieani commented 5 years ago

I'm open for PRs. Thanks for the issue.