[Haskell-begin] Re: For starters...

[Rafael Gustavo da Cunha Pereira Pinto]

I will use foldr max 0, because I want 0 for the empty list.



On Thu, Jul 17, 2008 at 12:09, Isaac Dupree <isaacdupree at charter.net> wrote:

> Marco Túlio Gontijo e Silva wrote:
>
>> Hi.
>>
>> Em Qui, 2008-07-17 às 11:42 -0300, Felipe Lessa escreveu:
>>
>>> f = sum &&& foldr max 0 >>> uncurry (-)
>>>
>>
>> You can replace
>>
>>> foldr max 0
>>>
>> with simply
>>
>>> foldr1 max
>>>
>> or even
>>
>>> maximum
>>>
>>
> If it's important that the function return 0 when given an empty list, then
> you don't want to use foldr1 or maximum.  But, if you don't need it to, then
> it may be sounder to have it fail on an empty list, because it's not
> particularly well-defined what it should return then.
>
> -Isaac
>
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-- 
Rafael Gustavo da Cunha Pereira Pinto
Electronic Engineer, MSc.
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