[Haskell-cafe] ANN: unordered-containers - a new, faster hashing-based containers library

[wren ng thornton]

On 2/23/11 4:42 PM, Sterling Clover wrote:
> A quick grep of some of my own source reveals that I've used M.size and S.size only to test for sizes equal to 1. So, for my purposes at least, an O(1) isSingleton operation would be just as useful as an O(1) size.

I agree, a fast isSingleton function would cover a very common use 
case--- especially for set-like containers.

-- 
Live well,
~wren