On Thu, 13 Feb 2014 19:06:45 -0500, timotheecour
<timothee.co...@gmail.com> wrote:
On Thursday, 13 February 2014 at 23:56:35 UTC, Timothee Cour
wrote:
how to iterate over an AA by key-value pair (tuple)?
use case:
avoid interrupting UFCS chains, eg:
foo.generate_aa.byKeyValue.filter!(a=>a[0].isLower).map!(a=>a[1]) ...
of course I could roll my own function but I was wondering if there's
already a way.
is there anything more efficient than this?
auto byKeyValue(T)(T a)if(isAssociativeArray!T){
return a.byKey.map!(b=>tuple(b, a[b]));
}
Of course. The a[b] lookup is significant in the complexity, it's
amortized constant, and the constant is not always small. Consider that
all keys and values are already stored in structs inside the AA. With
low-level access, it would be trivial to make an efficient tuple generator
that did not need to lookup values by keys.
-Steve
