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jim: I just asked about let/where in #haskell. there was no consensus
i'll appeal to a higher power, hold on.
On Tue, Feb 2, 2010 at 11:15 AM, Jim <ludflu@gmail.com> wrote:
> Hi Dan,
>
> Thanks for your talk last night. It was great to see some Haskell code doing
> some realistic stuff like hitting the DB. (As opposed to the more abstract
> Haskell example one generally encounters) Also the non-mystical approach to
> monadic operations is refreshing.
>
> I've been thinking about a couple items:
>
> 1. Tail Call Optimization in Haskell
>
> I'm quite certain that it works fine. See dons' comment
>
> http://www.reddit.com/comments/6xnk5/ive_got_two_weeks_of_vacation_coming_up_should_i/c055b9w
>
> Where it gets confusing is that often, my first run at a haskell tail
> recursive function lazily accumulates something against a very large list,
> resulting in a stack overflow. But that's due to inappropriate laziness, not
> lack of optimized tail recursion. Then I replace foldl with foldl' and
> things work out fine- strictly accumulating a lazy list.
> I think Mattias might have said something to this effect last night- "the
> two issues are orthogonal". However, my head was spinning too much from all
> the abstractions to process it.
>
> Re-reading the Real World Haskell section on "Strictness and Tail Recursion"
> (pg 571 in the printed version) it does seem that the issues are conflated,
> which is uncharacteristicaly confusing for this book.
>
> 2. Let vs. Where / Strict vs Lazy
>
> I can't find anything to support the idea that one is lazy and the other
> strict.
> http://www.haskell.org/haskellwiki/Let_vs._Where
>
> It seems like either one could be lazy or strict depending on how its coded.
>
> The major difference seems to the scope of the bindings: "let..in" is an
> expression, but "where" applies to the preceding block- which doesn't have
> to be an expression.
> Its strange that I've been able to use both without clearly understanding
> the difference...
>
> 3. I've found the "Hoogle" search engine very helpful.
>
> http://www.haskell.org/hoogle/
>
> If you just enter a type signature, it finds all the matching functions.
>
> --Jim
>
>
>
>
> On Mon, Feb 1, 2010 at 4:07 PM, Dan Mead <d.w.mead@gmail.com> wrote:
>>
>> Hey all
>>
>> My plan for tonight is to go over some slides about the language, walk
>> through some example code and get
>> people writing a bit of code. So bring your laptops!
>>
>> -Dan
>>
>> On Wed, Jan 27, 2010 at 3:28 PM, Hristo Asenov
>> <hristo.s.asenov@gmail.com> wrote:
>> > I will be able to be there as well.
>> >
>> > On Wed, Jan 27, 2010 at 2:19 PM, Nik Kolev <nkolev@gmail.com> wrote:
>> >>
>> >> i should be able to make it
>> >>
>> >> On Wed, Jan 27, 2010 at 10:53 AM, Aaron Feng <aaron.feng@gmail.com>
>> >> wrote:
>> >>>
>> >>> Hi All,
>> >>>
>> >>> I'm thinking about scheduling the Haskell workshop on Feb 1st. What
>> >>> do you guys think? I'll send out the RSVP again later
>> >>> if people are cool with it.
>> >>>
>> >>> Thanks,
>> >>>
>> >>> Aaron
>> >>
>> >
>> >
>
>
>
> --
> --Jim
>
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