Re: [GHC] #1347: warning message could be more helpful

2007-06-24 Thread GHC 
#1347: warning message could be more helpful
-+--
Reporter:  guest |Owner: 
Type:  bug   |   Status:  closed 
Priority:  normal|Milestone: 
   Component:  Compiler  |  Version:  6.6.1  
Severity:  normal|   Resolution:  invalid
Keywords:|   Difficulty:  Unknown
  Os:  Unknown   | Testcase: 
Architecture:  Unknown   |  
-+--
Changes (by igloo):

  * resolution:  = invalid
  * status:  new = closed

Comment:

 If you compile with `-Wall` (which I recommend!) (or `-fwarn-name-
 shadowing`) then, as well as the above warning, you will also get
 {{{
 Warning: This binding for `wM_DESTROY' shadows an existing binding
  In a case alternative
 }}}

-- 
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/1347
GHC http://www.haskell.org/ghc/
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[GHC] #1347: warning message could be more helpful

2007-05-10 Thread GHC 
#1347: warning message could be more helpful
---+
  Reporter:  guest |  Owner: 
  Type:  bug   | Status:  new
  Priority:  normal|  Milestone: 
 Component:  Compiler  |Version:  6.6.1  
  Severity:  normal|   Keywords: 
Difficulty:  Unknown   | Os:  Unknown
  Testcase:|   Architecture:  Unknown
---+
Code was:
 {{{
 case msg of
 wM_DESTROY - do
 sendMessage hwnd wM_QUIT 1 0
 return 0
 otherwise - defWindowProc (Just hwnd) msg wparam lparam
 }}}

 warning message was:

 {{{
 Warning: Pattern match(es) are overlapped
  In a case alternative: otherwise - ...
 }}}

 It took me a long time to realize that wM_DESTROY was being interpreted as
 a new variable name shadowing the imported constant.  The compiler
 realizes that something is probably wrong (overlapped patterns).  It could
 further check and see that wM_DESTROY is shadowing an already existing
 binding and give a messages like this:

 {{{
 Warning: Pattern match(es) are overlapped
  In a case alternative: otherwise - ...
  Hint: Are you sure you want to shadow the existing binding for
 wM_DESTROY?
 }}}

-- 
Ticket URL: http://hackage.haskell.org/trac/ghc/ticket/1347
GHC http://www.haskell.org/ghc/
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