
#12170: Add flag to control whether out of scope variables should be deferred with -fdefer-typed-holes -------------------------------------+------------------------------------- Reporter: mpickering | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Compiler | Version: 8.0.1 Keywords: newcomer | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: #10569 Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- As a result of #10569, out of scope variables are turned into special type holes so that type information of the variable can be attached to the error message. However, this causes problems when used with `-fdefer-typed-holes` as scope errors have been turned into type errors and are now deferred when using this flag. Richard sums up the situation, "Even if someone is deferring type errors, I imagine most people don't want to defer scope errors". It would be good to add a flag which controls whether out of scope variables are also deferrable when used with existing deferral flags. Goal: Add a flag ` -fdefer-out-of-scope-variables` which controls whether out of scope variables are deferred when using `-fdefer-typed-holes`. It should be turned off by default. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12170 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler