Isaac Dupree ml at
Sun Jul 26 13:52:26 EDT 2009

Sean Leather wrote:
> To me, the syntax is not actually stricter, just that the precedence for
> labeled field construction, update, & pattern is lower. What is the
> effective new precedence with this change? Previously, it was 11 (or simply
> "higher than 10"). Is it now equivalent to function application (10)?

maybe it's equivalent "infix 10" (not infixr/infixl) so that it doesn't 
associate with function application (or itself) at all, either left- or 
right- ly.  I didn't understand by reading the patch to the report...

Ian Lynagh wrote:
> I think that even an example of where parentheses are needed would be
> noise in the report. I don't think the report generally gives examples
> for this sort of thing, e.g. I don't think there's an example to
> demonstrate that this is invalid without parentheses:
>     id if True then 'a' else 'b'

Well that's also something that in my opinion there *should* be an 
example for, because IMHO there's no obvious reason why it's banned 
(whereas most of the Report's syntax repeats things that should be 
obvious and necessary to anyone who knows Haskell).


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