#2456: For higher kinds, instance declarations need quantification in the context -------------------------------+-------------------------------------------- Reporter: ronwalf | Owner: Type: feature request | Status: new Priority: normal | Milestone: _|_ Component: Compiler | Version: 6.9 Resolution: | Keywords: Os: Unknown/Multiple | Architecture: x86 Failure: None/Unknown | Difficulty: Unknown Testcase: | Blockedby: Blocking: | Related: -------------------------------+-------------------------------------------- Comment(by goldfire): In response to the type system question: Essentially, yes, if something is expressible in FC, then it must* be good. But, I know of two loopholes in FC: unsafe coercions (we all knew that), and the !GeneralizedNewtypeDeriving bug (see #1496, #4846, which seem, to me, to be duplicates). *FC is a complicated beast these days, and though we've proved it type- safe in theory, we can't be sure in practice. :) -- Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/2456#comment:9 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler