> On Jan 8, 2018, at 6:29 PM, Ben Cohen via swift-evolution 
> <swift-evolution@swift.org> wrote:
> There exists in the standard library a type `DictionaryLiteral` that deserves 
> naming re-consideration before we declare ABI Stability, because it’s 
> confusingly misnamed, being neither a Dictionary (it doesn’t provide 
> key-based lookup of values) nor a Literal. 
> Instead, it’s just an immutable collection of key-value pairs you can create 
> _from_ a literal.
> I’m canvassing for opinions on what it ought to be called.  Some suggestions 
> so far:
> - `AssociationCollection`: Following the term of art from some other 
> languages. Slightly obscure-sounding to developers not already familiar. Also 
> “association” and “associative” are confusingly similar, which brings back 
> the is-this-a-dictionary problem.
> - `KeyValueCollection`: Problematic because key-value comes up in a totally 
> different context in Cocoa.
> - `PairCollection`: “Pair” is kinda nondescript.
> - Do nothing. It’s not so bad.

Agreed so far, and I'd like to add CollectionOfPairs to the list.

Some more fun facts about this type:
- Besides Dictionary, it's the only other type in the standard library that is 
expressible by a dictionary literal
- Unlike Dictionary, it *does* maintain the order of its pairs
- Unlike Dictionary (part 2), it *doesn't* require the first element of the 
pairs to be Hashable


> The old name can live on indefinitely via a typealias (which has no ABI 
> consequences, so could be retired at a later date once everyone has had 
> plenty of time to address the deprecation warnings). Removing it as not 
> carrying its weight (and instead using `[(Key,Value)]`, which is basically 
> what it’s a wrapper for) is probably off the table for source stability 
> reasons.
> Any further thoughts welcome.
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