#393: functions without implementations -------------------------------------+------------------------------------- Reporter: c_maeder | Owner: simonpj Type: feature request | Status: new Priority: normal | Milestone: _|_ Component: Compiler (Type | Version: None checker) | Keywords: Resolution: None | Architecture: Unknown/Multiple Operating System: Unknown/Multiple | Difficulty: Moderate (less Type of failure: None/Unknown | than a day) Test Case: | Blocked By: Blocking: | Related Tickets: -------------------------------------+------------------------------------- Comment (by simonpj): I suggest * A language extension flag `-XUndefinedFunctions` or something * In the renamer you'll have to arrange to create a binder for a signature that lacks a corresponding binding; and give an warning (rather than an error) for such signatures. * I suggest that you actually add the definition `f = error "Missing definition for f"` (or whatever) in the desugarer. GHC generally tries NOT to mess with the source code until desugaring, so that you can always show exactly what the user wrote. Happy to discuss when you get a bit further Simon -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/393#comment:16 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler