#8710: Overlapping patterns warning misplaced -------------------------------------+------------------------------------- Reporter: goldfire | Owner: Type: bug | Status: new Priority: low | Milestone: Component: Compiler | Version: 7.7 Resolution: | Keywords: | PatternMatchWarnings Operating System: Unknown/Multiple | Architecture: Type of failure: Incorrect | Unknown/Multiple warning at compile-time | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Phab:D1910 Wiki Page: | -------------------------------------+------------------------------------- Comment (by simonpj):
If we print a separate warning for every redundant clause it may become overwhelming
Really? There are a few artificial examples in the testsuite, but I'd have thought that one error per redundant equation would be ok. But still, I'd really like the common case of one redundant equation to look like {{{ Bug.hs:24:3: warning: -- Note correct line number Pattern match(es) are redundant In an equation for ‘show’: len _ = ... (at Bug.hs:24:3) }}} Or maybe even {{{ Bug.hs:24:3: warning: Pattern match(es) are redundant In an equation for ‘show’: len _ = ... -- No need to duplicate here }}} If there are more than one, then adding the individual locations is good {{{ Bug.hs:24:3: warning: Pattern match(es) are redundant In an equation for ‘show’: len _ = ... (at Bug.hs:24:3) len _ = ... (at Bug.hs:25:3) }}} but the herald should mention the first. Can't be hard, I guess. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8710#comment:8 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler