RFR: 8314502: Change the comparator taking version of GrowableArray::find to be a template method [v2]

[Stefan Karlsson]

On Fri, 25 Aug 2023 09:45:09 GMT, Johan Sjölen <jsjolen at openjdk.org> wrote:

>> This code looks similar to a capturing lambda. Would an alternative be to use that instead and let the calling code be changed to:
>> 
>> 
>>   int i = lgrp_spaces()->find([&](LGRPSpace* space) {
>>     return space->lgrp_id() == lgrp_id;
>>   });
>> 
>> 
>> Alternatively:
>> 
>>   auto matches_lgrp_id = [&](LGRPSpace* space) {
>>     return space->lgrp_id() == lgrp_id;
>>   };
>>   
>>   int i = lgrp_spaces()->find(matches_lgrp_id);
>
> We could just as well do a capturing lambda here, yes. Then we'd have:
> 
> ```c++
> template<F>
> int find(F finder);
> 
> 
> It'd be a template instead of function pointer since it's a capturing lambda and  `std::function` is not permitted in Hotspot AFAIK. 
> 
> As an aside, to clarify for readers: There's a `&` missing in the capture list of your examples.

Updated in-place

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/15418#discussion_r1305517877