sort associative array by key

[dsmith]

On Friday, 23 November 2012 at 18:24:07 UTC, Timon Gehr wrote:
> On 11/23/2012 07:09 PM, dsmith wrote:
>> What is the best way to have a function sort an associative 
>> array by
>> key?  The following yields a conversion error.
>>
>> double[string] aa_sort(double[string] aa) {
>>   return aa.keys.sort;
>> }
>>
>>
>
> A hash table is unsorted by definition. What is it that you 
> want to do exactly?
>
> The following will generate a newly allocated dynamic array of 
> key-value pairs, sorted by key:
>
> import std.algorithm, std.typecons;
>
> Tuple!(string, double)[] aa_sort(double[string] aa){
>     typeof(return) r=[];
>     foreach(k,v;aa) r~=tuple(k,v);
>     sort!q{a[0]<b[0]}(r);
>     return r;
> }

Suppose the string is of the format 201207, 21208, ...
So aa["201207"] == 123.45

How do you parse the tuple for the key and the value?