JuliaDiff
document ReverseDiff.jl integration's need to opt-in
From Slack:
[Fredrik Bagge Carlson](https://app.slack.com/team/UJ7DVTVQ8) [Today at 3:48 PM](https://julialang.slack.com/archives/C6G240ENA/p1646063331166529)
I'm looking at
https://juliadiff.org/ChainRulesCore.jl/stable/index.html#ChainRules-roll-out-status
and it seems like ReverseDiff.jl is supposed to work with ChainRules, but i can't seem to figure out how, my rules are never called
4 replies
[Seth Axen](https://app.slack.com/team/UHDQQ4GN6):axe: [7 minutes ago](https://julialang.slack.com/archives/C6G240ENA/p1646063442894469?thread_ts=1646063331.166529&cid=C6G240ENA)
By default ReverseDiff opts out of all rules for now. Use https://github.com/JuliaDiff/ReverseDiff.jl/blob/df0067465ca436b05377054ac7a184da691db1a3/src/macros.jl#L298-L315 to opt-in on a per-rule basis.
[Fredrik Bagge Carlson](https://app.slack.com/team/UJ7DVTVQ8) [6 minutes ago](https://julialang.slack.com/archives/C6G240ENA/p1646063506399249?thread_ts=1646063331.166529&cid=C6G240ENA)
ok thanks for answering :slightly_smiling_face: Perhaps that should be made clear in the docs for chain rules? I couldn't find anything in the docs for RD either
[Seth Axen](https://app.slack.com/team/UHDQQ4GN6):axe: [5 minutes ago](https://julialang.slack.com/archives/C6G240ENA/p1646063571928219?thread_ts=1646063331.166529&cid=C6G240ENA)
Yeah, the CR docs could be made more specific there. RD should document it. Not certain if this is considered an API macro.
[Fredrik Bagge Carlson](https://app.slack.com/team/UJ7DVTVQ8) [2 minutes ago](https://julialang.slack.com/archives/C6G240ENA/p1646063717720879?thread_ts=1646063331.166529&cid=C6G240ENA)
It looks like the macro has some scoping issue
julia> ControlSystems
ControlSystems
julia> ReverseDiff.@grad_from_chainrules RobustAndOptimalControl.hinfnorm2(T::ControlSystems.StateSpace{Continuous, ReverseDiff.TrackedReal})
ERROR: UndefVarError: ControlSystems not defined
Stacktrace:
[1] top-level scope
@ ~/.julia/packages/ReverseDiff/Y5qec/src/macros.jl:324
It works if I do
@eval ReverseDiff using ControlSystems
which I guess is an indication that the macro is missing some esc
Can you open an issue in ReverseDiff? (In general, I'm not surprised, I think I came across some issues with the macros in ReverseDiff a while ago but didn't have time to fix it and could work around it.)
Maybe the documentation issue is an issue of ReverseDiff (as well)? I.e., maybe the issue should be moved to ReverseDiff?
It should have a brief mention in the CRC docs, (Since we have now done https://github.com/JuliaDiff/ChainRulesCore.jl/pull/514/files) but most of the docs on it should be in ReverseDiff.jl
A docstring exists but is not included in the documentation: https://github.com/JuliaDiff/ReverseDiff.jl/pull/196