What determines if an algorithm goes in std.algorithm or std.range

[aliak]

Alo, I'm wondering how phobos devs view or determine what goes in 
to std.algorithm and what goes in to std.range.

To me some of them are quite obvious - well, most things can 
arguably be an algorithm. But for example "refRange" is clearly a 
range specific thing, but "transpose" is not. And things that 
create ranges from nothing also may "clearly" belong in the range 
module? (e.g. iota, generate and recurrence)

Also curious, are there any github PRs in phobos where certain 
algorithms were discussed as going in to where and what the 
reasonings were?

cheers
- Ali