patch applied (haskell-prime-status): add ""Make $ left associative, like application"

Dan Weston westondan at
Wed Apr 23 20:11:47 EDT 2008

John Meacham wrote:
> On Wed, Apr 23, 2008 at 09:52:11AM -0700, Simon Marlow wrote:
>> The problem with this is that
>>   f !x y
>> would associate differently in an expression than it does on the left hand 
>> side of an equation, where ! is the prefix bang-pattern operator. To make 
>> this consistent we'd have to make ! a prefix operator in expressions, or 
>> give it the same precedence as function application; both mean a new 
>> extension.
> Hmm.. that is another possible solution to the ~ ! - thing, have ~ and !
> be prefix operators in general. with ~ meaning 'negate' in expressions.
> then parsing is the same everywhere.

Do prefix operators bind more or less tightly than infix operators? 
Either way, one of the two expressions (~2^3) or (~y$z) will parse 
somewhat unintuitively.

I would expect these to mean ~(2^3) and (~y) $ z respectively.


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