[Haskell-cafe] Why is $ right associative instead of leftassociative?

Brian Hulley brianh at metamilk.com
Sat Feb 4 16:15:20 EST 2006

Stefan Holdermans wrote:
> Hash: SHA1
> Brian wrote:
>> I think the mystery surrounding :: and : might have been that
>> originally people thought type annotations would hardly ever be
>> needed whereas list cons is often needed, but now that it is
>> regarded as good practice to put a type annotation before every top
>> level value binding, and as the type system becomes more and more
>> complex (eg with GADTs etc), type annotations are now presumably far
>> more common than list cons so it would be good if Haskell Prime
>> would swap these operators back to their de facto universal
>> inter-language standard of list cons and type annotation
>> respectively.
> I don't think Haskell Prime should be about changing the look and
> feel of the language.

Perhaps it is just a matter of aesthetics about :: and :, but I really feel 
these symbols have a de-facto meaning that should have been respected and 
that Haskell Prime would be a chance to correct this error. However no doubt 
I'm alone in this view so fair enough - it's just syntax after all and I can 
run my own programs through a pre-processor if I want them the other way 
round... :-)

Regards, Brian. 

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