Sort Associative Array by Key

[Alexander Zhirov]

> foo.byPair
>  .array
>  .sort!((a, b) => a.key < b.key)
>  .map!(a => a.value);

Is it possible to specify in `map` to return the result `[a.key] 
= a.value`? To make the result look like `[key:[val], key:[val]]`