byKey and byValue: properties or methods?

[Steven Schveighoffer]

On Tue, 17 Jan 2012 19:02:03 -0500, Nick Sabalausky <a at a.a> wrote:

> "Alvaro" <alvaroDotSegura at gmail.com> wrote in message

>>
>> Oops. Yes, thanks.
>>
>> So, not bad. In those [infrequent, I'd say] cases needing an array one
>> would do:
>>
>>  auto keys = array(aa.keys);
>>
>
> My thoughts exactly. The current .keys made sense back in the days before
> ranges, std.algorithm, etc, but not so much anymore. Vote++

There is one significant problem with changing aa.keys to be a lazy range  
instead of an array.  This is valid code (and does exist in the wild):

foreach(k; aa.keys)
{
    if(shouldRemove(k))
       aa.remove(k);
}

This would silently start crashing programs if we changed the behavior of  
keys.

I don't see any way around this...

-Steve