A reasonable suggestion, but I'm afraid I don't want
to make structural changes to the Report.

Simon

| -----Original Message-----
| From: Mark Tullsen [mailto:[EMAIL PROTECTED]] 
| Sent: 27 September 2001 20:35
| To: Simon Peyton-Jones
| Cc: [EMAIL PROTECTED]
| Subject: Re: Haskell report (August release)
| 
| 
| Simon,
| 
| Here's a minor quibble with the organization of the Report 
| and Library, not with the content.  Sorry if this has been 
| brought up before.
| 
| In section 4.3.3, Derived Instances, of the Report there is
| 
|   The only classes in the Prelude for which derived instances are
|   allowed are Eq, Ord, Enum, Bounded, Show, and Read, all mentioned in
|   Figure 5, ...  Classes defined by the standard libraries may also be
|   derivable.
| 
| In the introduction to the Library Report there is
| 
|   Classes defined in libraries may be derivable. This report includes
|   the derivation of such classes when appropriate.
| 
| Now, unless I missed something, the only class in the Library 
| Report which is derivable is Ix.
| 
| I would argue for bringing the Ix class into the Report for 
| these reasons
|  
|   * One does not have to search through the Library Report to 
| determine
|     what is derivable.
| 
|   * I think one would expect that the Libraries contain stuff 
| that could be
|     implemented in Haskell by the user.  Until Haskell has 
| the ability 
|     to allow for user-defined derivable classes, Ix cannot be
|     defined by the user.
| 
| - Mark
| 

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