n + k patterns

[Simon Peyton-Jones]

Good point.  Fixed in the head, but not in 6.0

Thanks

Simon

| -----Original Message-----
| From: glasgow-haskell-bugs-admin at haskell.org
[mailto:glasgow-haskell-bugs-admin at haskell.org] On
| Behalf Of Ralf Hinze
| Sent: 28 May 2003 20:40
| To: GHC bugs
| Subject: n + k patterns
| 
| GHCi infers for
| 
| > fac 0                         =  1
| > fac (n + 1)                   =  (n + 1) * fac n
| 
| the following type
| 
|   / _ \ /\  /\/ __(_)
|  / /_\// /_/ / /  | |      GHC Interactive, version 5.04.2, for
Haskell 98.
| / /_\\/ __  / /___| |      http://www.haskell.org/ghc/
| \____/\/ /_/\____/|_|      Type :? for help.
| 
| Loading package base ... linking ... done.
| Loading package haskell98 ... linking ... done.
| Compiling Main             ( Fac.lhs, interpreted )
| Ok, modules loaded: Main.
| *Main> :t fac
| forall a. (Num a, Ord a) => a -> a
| 
| The Report, however, states that
| 
| 	3.17.2  Informal Semantics of Pattern Matching
| 	<...>
| 	An n+k pattern can only be matched against a value in the class
Integral.
| 
| Cheers, Ralf
| 
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