Suggestion: Syntactic sugar for Maps!

Thomas Davie tatd2 at
Thu Nov 27 16:14:43 EST 2008

On 27 Nov 2008, at 19:59, circ ular wrote:

> I suggest Haskell introduce some syntactic sugar for Maps.
> Python uses {"this": 2, "is": 1, "a": 1, "Map": 1}
> Clojure also use braces: {:k1 1 :k2 3} where whitespace is comma but
> commas are also allowed.
> I find the import Data.Map and then fromList [("hello",1), ("there",
> 2)] or the other form that I forgot(because it is to long!) to be to
> long...
> So why not {"hello": 1, "there": 2} ?

In a similar vein, I suggest not only to not do this, but also for  
Haskell' to remove syntactic sugar for lists (but keep it for strings)!

I have two (three if you agree with my opinions on other parts of the  
language) reasons for this:
1) It's a special case, that doesn't gain anything much.  [a,b,c,d] is  
actually only one character shorter and not really any clearer than  
2) Removing it would clear up the ',' character for use in infix  
3) (requiring you to agree with my opinions about tuples) it would  
allow for clearing up the tuple type to be replaced with pairs  
instead.  (,) could become a *real* infix data constructor for pairs.   
This would make us able to recreate "tuples" simply based on a right  
associative (,) constructor.  I realise there is a slight issue with  
strictness, and (,) introducing more bottoms in a "tuple" than current  
tuples have, but I'm sure a strict version of the (,) constructor  
could be created with the same semantics as the current tuple.

Just my 2p


Tom Davie

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