[Haskell-cafe] Re: Why is $ right associative insteadofleftassociative?

Paul Hudak paul.hudak at yale.edu
Sun Feb 5 20:27:36 EST 2006

Brian Hulley wrote:
> ... I didn't realise that list comprehension syntax was not just a 
> sugar for the equivalent do expression but I see now that it is indeed 
> translated differently, bypassing monads altogether, which of course is 
> confusing but understandable if monads were only thought up after list 
> comprehensions were already in the language.

Here's the brief history with respect to this issue:

Apr 1990: Haskell Report 1.0, list comps, but no monads.
May 1996: Haskell Report 1.3, monads appear.
Apr 1997: Haskell Report 1.4, list comps made applicable to
           arbitrary monads.
Feb 1999: Haskell 98 Report, list comps reverted to just lists.


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