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TypeScript dependent types and function bivariance (reperiendi.wordpress.com)
19 points by metaweta 1965 days ago
1 comments

> TypeScript now supports

What does "now" mean here? The sample code works fine on 3.3 (the earliest version I could select on the playground, I'm sure it works on earlier versions too), released in January 2019.

Conditional types were introduced in TypeScript 2.8, released March 2018. The sample code from the documentation dates back to 2014: https://web.archive.org/web/20140407071740/http://www.typesc...