enum-indexed arrays

["Nordlöw" via Digitalmars-d-learn]

On Saturday, 20 September 2014 at 20:43:28 UTC, bearophile wrote:
> In D currently that "int[I]" is an associative array with I 
> index and int values. So in another post I have suggested 
> another syntax.

Couldn't we simply add an optimization pass that CT-introspects 
the enumerators of an enum-indexed AA and represent it internally 
as a lookup-table if the enumerator values are adjacent (enough)?