help from the community?

Malcolm Wallace Malcolm.Wallace at cs.york.ac.uk
Thu Feb 1 16:53:12 EST 2007


On 1 Feb 2007, at 21:31, Jacques Carette wrote:

> Stephanie Weirich wrote:
>> I don't think we want to allow types like:
>>
>>     forall . Int   or     forall a b. Int
>>
>> These types are mostly bugs. Furthermore, rejecting them doesn't  
>> limit expressiveness:
>
> If you restrict yourself to programs entirely written by humans, I  
> agree completely.  But if you consider programs written by programs  
> (say Template Haskell to be specific, but it could be via many  
> other means), such degenerate types occur rather often.

I find the "program-generated code" argument rather weak.  In that  
past it was used to justify all kinds of minor horrors like excess  
commas in lists and so on.  But if one can write a program to  
generate syntactically valid but ugly code, one can easily spend a  
little extra effort on making the result beautiful too.  After all,  
which is the more difficult task - devising the auto-coding schema,  
or pretty-printing?  There is no reason to accept ugly coding  
practices just because it makes the auto-coder's job slightly  
simpler.  That only encourages humans to use sloppy practices in hand- 
written code as well.

Regards,
     Malcolm


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