现在是否允许在实例声明中使用类型签名而不需要 InstanceSigs 语言扩展？
Are type signatures now permitted in instance declarations without needing the InstanceSigs language extension?
我注意到，当我将 VS Code 与当前版本的 Haskell（GHC 9.2.1 和 HLS 1.6.1.0）一起使用时，在我的实例声明中写入类型签名时不再收到错误，即使我没有包含 {-# LANGUAGE InstanceSigs -#} 扩展名。
最近是否对 Haskell 进行了更改以默认允许实例签名？
GHC 9.2.1 默认启用 GHC2021。
The GHC2021 language is supported now. It builds on top of Haskell2010, adding several stable and conservative extensions, and removing deprecated ones. It is now also the “default” language set that is active when no other language set, such as Haskell98 or Haskell2010, is explicitly loaded (e.g via Cabal’s default-language).
https://downloads.haskell.org/~ghc/9.2.1/docs/html/users_guide/9.2.1-notes.html
GHC2021 语言启用 InstanceSigs.
https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0380-ghc2021.rst
我注意到，当我将 VS Code 与当前版本的 Haskell（GHC 9.2.1 和 HLS 1.6.1.0）一起使用时，在我的实例声明中写入类型签名时不再收到错误，即使我没有包含 {-# LANGUAGE InstanceSigs -#} 扩展名。
最近是否对 Haskell 进行了更改以默认允许实例签名？
GHC 9.2.1 默认启用 GHC2021。
The GHC2021 language is supported now. It builds on top of Haskell2010, adding several stable and conservative extensions, and removing deprecated ones. It is now also the “default” language set that is active when no other language set, such as Haskell98 or Haskell2010, is explicitly loaded (e.g via Cabal’s default-language). https://downloads.haskell.org/~ghc/9.2.1/docs/html/users_guide/9.2.1-notes.html
GHC2021 语言启用 InstanceSigs.
https://github.com/ghc-proposals/ghc-proposals/blob/master/proposals/0380-ghc2021.rst