#10653: PatternSynonyms should be imported/exported as part of the wildcard notation -------------------------------------+------------------------------------- Reporter: gridaphobe | Owner: mpickering Type: feature request | Status: new Priority: high | Milestone: 8.0.1 Component: Compiler | Version: 7.11 Resolution: | Keywords: pattern | synonyms Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Revisions: -------------------------------------+------------------------------------- Comment (by mpickering): Reid, Your example is not a valid bidirectional synonym as the RHS contains a view pattern. You are right that such synonyms can exist though. Here is an example. {{{ {-# LANGUAGE PatternSynonyms, ViewPatterns #-} module Foo where class C f where build :: a -> f a destruct :: f a -> a pattern P :: () => C f => a -> f a pattern P x <- (destruct -> x) where P x = build x }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/10653#comment:18 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler