migration/8.6.md

@@ -19,10 +19,16 @@ importGHC.TypeLitsf::Proxy m ->Proxy n ->Proxy(m * n)f__=Proxy
 ```
 
 
-Will not typecheck if `StarIsType` is enabled, since `m * n` is treated as if one had written `m Type n`. There are two ways to adapt to this:
+Will not typecheck if `StarIsType` is enabled, since `m * n` is treated as if one had written `m Type n`. There are several ways to adapt to this:
 
 1. Use `*` qualified (e.g., `Proxy (m GHC.TypeLits.* n`). This approach is compliant with the GHC three-release policy, as it does not require CPP to support older GHCs.
-1. Enable the `NoStarIsType` extension. Since `(No)StarIsType` did not exist on older GHCs, this approach will require CPP in order to support older compilers.
+1. Enable the `NoStarIsType` extension using a `LANGUAGE` pragma. Since `(No)StarIsType` did not exist on older GHCs, this approach will require CPP in order to support older compilers.
+1. Conditionally enable the `NoStarIsType` extension using Cabal's `default-extensions` field, like this:
+
+  ```wiki
+    if impl(ghc >= 8.6)
+      default-extensions: NoStarIsType
+  ```
 
 ### `MonadFailDesugaring` by default