iota where step is a function

[Rene Zwanenburg]

On Wednesday, 24 May 2023 at 16:39:36 UTC, Ben Jones wrote:
> Is there a range like iota in phobos where step is a function?  
> I want to specify begin/end and have the "step" be next = 
> fun(prev).  Should be easy to write, but don't want to reinvent 
> the wheel.

I think you’re looking for either recurrence() or sequence(), 
also defined in std.range.