[Haskell] Rank-N types with (.) composition

Tyson Whitehead twhitehead at gmail.com
Wed Feb 11 00:02:51 UTC 2015


On February 10, 2015 17:44:54 Dan Doel wrote:
> Really, I think the least ad-hoc solution (other than a hypothetical
> best-of-both-worlds inference algorithm) would be to allow code like:
> 
>     runST do ...
> 
> where you can apply expressions directly to certain syntactic constructs
> without an operator in between. I suspect the majority of cases where
> 'runST $' is used are followed by a 'do,' and not having the remaining ones
> wouldn't be nearly as painful to use with parentheses (since they likely
> wouldn't be multi-line). And this extension is desirable for other reasons
> as well (though I can't recall any specifics off the top of my head).

I would like that a lot even if not for this case.

It's always seemed kind of silly that you have to throw in a $.

Cheers!  -Tyson


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