range methods on associative arrays

[WebFreak001]

On Saturday, 2 July 2022 at 21:18:06 UTC, Steven Schveighoffer 
wrote:
> On 7/2/22 4:14 PM, WebFreak001 wrote:
>> a lot of range methods, such as `filter`, `any`, `all`, 
>> `count`, `each`, etc. would be useful on associative arrays, 
>> taking in key and value, returning a processed .byKeyValue 
>> range.
>> 
>> I would suggest, at least for phobos v2, we should have these 
>> functions automatically call `.byKeyValue` on maps and there 
>> should be support for lambdas with 2 arguments there, which 
>> automatically unwrap key and value (and possibly all tuples 
>> actually)
>> 
>> What do you think?
>> 
>> ```d
>> map.each!((key, value) { /* like a foreach, but functional 
>> style */ });
>> 
>> bool hasId = map.any!((key, value) => key == "id" && value !is 
>> null);
>> ```
>> 
>> for this I think the implementation would basically boil down 
>> to:
>> 
>> - implicitly call `.byKeyValue` in the map-accepting range 
>> methods
>> - allow tuples and the KeyValue pair to be extended into 
>> multiple parameters on CT lambdas that have multiple arguments
>> 
>> Users wanting to only use keys or only values can still use 
>> .byKey or .byValue.
>
> This idea misunderstands what a range is.
>
> In order for an AA to be considered a "range", each popFront 
> should remove the element from the AA.
>
> We don't want that. Just use the range accessors.
>
> -Steve

arrays/slices are also not ranges and get special-cased (or at 
least have compatibility functions in std.range.primitives) to be 
used with range code, I don't see any reason why not to do this 
with maps as well, which are a first class feature of the 
language.