[Haskell-cafe] Richer (than ascii) notation for haskell source?

[Brandon S. Allbery KF8NH]

On 2008 May 14, at 15:00, Andrew Coppin wrote:
> Brandon S. Allbery KF8NH wrote:
>>
>> On 2008 May 14, at 14:32, Andrew Coppin wrote:
>>> Personally, I'd just like to be able to get rid of "->", "\" and  
>>> other such hacks. Would it be possible to amend GHC so that it  
>>> accepts "->" and [whatever the Unicode codepoint for "left arrow"  
>>> is] and treats both the same?
>>
>> Both of those are already there, along with some others.  It's been  
>> discussed here but I can't find it in the 6.8.2 manual....  (boo,  
>> hiss)  -XUnicodeSyntax
>
> Mmm, I can see I'm going to have to test this... [That is, just as  
> soon as I figure out how to even type in obscure Unicode symbols...]


And, for future reference:

> #if __GLASGOW_HASKELL__ >= 605
>        ,("?\x88?",   ITdcolon, unicodeSyntaxEnabled)
>        ,("?\x87\x92",   ITdarrow, unicodeSyntaxEnabled)
>        ,("?\x88\x80",   ITforall, \i -> unicodeSyntaxEnabled i &&
>                                 explicitForallEnabled i)
>        ,("?\x86\x92",   ITrarrow, unicodeSyntaxEnabled)
>        ,("?\x86\x90",   ITlarrow, unicodeSyntaxEnabled)
>        ,("?\x8b?",   ITdotdot, unicodeSyntaxEnabled)
>         -- ToDo: ideally, ?\x86\x92 and ?\x88? should be "specials",  
> so that the
> y cannot
>         -- form part of a large operator.  This would let us have a  
> better
>         -- syntax for kinds: ?\x91?\x88?*?\x86\x92* would be a legal  
> kind signat
> ure. (maybe).
> #endif

So ∷, ⇒, ∀, →, ←, ‥ currently supported.  Others clearly  
could be, but probably not as built-in syntax (Prelude.Unicode: let ×  
= *, anyone?).

-- 
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery at kf8nh.com
system administrator [openafs,heimdal,too many hats] allbery at ece.cmu.edu
electrical and computer engineering, carnegie mellon university    KF8NH