An extension that GHC provides, and therefore part of the effective standard, is Safe Haskell (http://www.haskell.org/ghc/docs/7.4.2/html/users_guide/safe-...). A Safe (compiled with -XSafe, containing the LANGUAGE Safe pragma, or inferred) module may not define any manual instances of Typeable.
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An extension that GHC provides, and therefore part of the effective standard, is Safe Haskell (http://www.haskell.org/ghc/docs/7.4.2/html/users_guide/safe-...). A Safe (compiled with -XSafe, containing the LANGUAGE Safe pragma, or inferred) module may not define any manual instances of Typeable.