A case for valueless AA's?

[Andrej Mitrovic]

A use case for this could be a file system search:

    void[string] names;  // unique names to find
    string[] results;

    foreach (string name; dirEntries(curdir, SpanMode.deep))
    {
        if (name.basename in names)
            results ~= name;
    }

With string arrays the `if` check might slow things down.