Fastest way to "ignore" elements from array without removal

[Paul Backus]

On Tuesday, 16 February 2021 at 09:08:33 UTC, z wrote:
> Does filter support multiple arguments for the predicate?(i.e. 
> using a function that has a "bool function(T1 a, T2 b)" 
> prototype)

I am not sure exactly what you are asking here, but you can 
probably accomplish what you want by combining filter with 
std.range.chunks or std.range.slide.

http://phobos.dpldocs.info/std.range.chunks.html
http://phobos.dpldocs.info/std.range.slide.html

> If not could still implement the function inside the loop but 
> that would be unwieldy.
> And does it create copies every call? this is important because 
> if i end up using .filter it will be called a 6 to 8 digit 
> number of times.

filter does not create any copies of the original array. The same 
is true for pretty much everything in std.range and std.algorithm.