Type-Strict Indexes: IndexedBy

[anonymous via Digitalmars-d-learn]

On Tuesday, 17 February 2015 at 19:46:09 UTC, Nordlöw wrote:
> Superb! I'd like to see this getting into std.typecons.
>
> Having this in the language will attract (more) Ada programmers 
> to D.
>
> Should I do PR for std.typecons.[iI]ndexedBy?

I'm not familiar with Ada, and I don't immediately see what 
indexedBy is good for. So maybe gather some examples where it's 
beneficial, before going for Phobos.