Feature: Statically checked declaration-site variance

This is the tracking issue for introducing a statically checked mechanism for declaration-site variance in Dart. Background: The original request motivating this kind of feature is #213; the initial proposal for declaration-site invariance is #214. The initial proposal for the related feature known as use-site invariance is #229, and the corresponding tracking issue is #753. Note that this issue does come up in practice. Here are a few examples gathered since April 2023. Many of them contain interesting discussions! - https://github.com/dart-lang/sdk/issues/63960 - https://github.com/dart-lang/sdk/issues/62825 - https://github.com/dart-lang/sdk/issues/61814 - https://github.com/dart-lang/sdk/issues/61312 - https://github.com/dart-lang/sdk/issues/60742 - https://github.com/dart-lang/sdk/issues/60288 - https://github.com/dart-lang/sdk/issues/60009 - https://github.com/dart-lang/language/issues/4230 - https://github.com/dart-lang/sdk/issues/57799 - https://github.com/dart-lang/sdk/issues/57052 - https://github.com/dart-lang/sdk/issues/56231 - https://github.com/dart-lang/sdk/issues/55427 - https://github.com/dart-lang/sdk/issues/55321 - https://github.com/dart-lang/sdk/issues/55315 - https://github.com/dart-lang/sdk/issues/54439 - https://github.com/dart-lang/sdk/issues/54200 - https://github.com/dart-lang/sdk/issues/54122 - https://github.com/dart-lang/sdk/issues/54108 - https://github.com/dart-lang/sdk/issues/52168 - https://github.com/dart-lang/sdk/issues/52249 - https://g

Posted by eernstg on Aug 14, 2019, 2:07 PM

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• github (Software)

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