[Haskell] confusing language in report and a bug in (ghc|hugs)

John Meacham john at repetae.net
Thu Jul 29 15:49:49 EDT 2004


On Thu, Jul 29, 2004 at 09:06:05AM +0100, Simon Peyton-Jones wrote:
> I'm inclined to think John is right, thought the Report could be
> clearer.

Yeah, I agree that is the right behavior, the main reason for confusion
was the (para)phrase(d) 'just like normal matching except', as my first
thought was that just like normal matching implied 'left-to-right' as
written in the pattern and that is what the exception is refering too.

in any case, the errata makes it quite clear. The bug in ghc didn't help
my understanding though :)

Also, another small bug in the report:

in chapter 4,
the fixity table is refered to as table 4.1 in the text, but is labeled 'table 2'.
It is also missing the (=<<) operator which is defined in the prelude. 


out of curiosity, when is the =<< useful? I have never used it and I am
wondering if it could have been making my life easier. Perhaps I have
just not been trained to recognize when it should be used.

It is amazing what little things you pick up when you sit down and read
the report as if it were a novel :)
        John


-- 
John Meacham - ⑆repetae.net⑆john⑈ 


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