generic rrule for all getfield

[oxinabox]

If I am correct: the rrule for getfield is always:

function rrule(::typeof(getfield), val::P, field::Symbol) where P
    getfield_pullback(dy) = NO_FIELDS, Composite{P}(; (field => dy,)...)
    return getfield(val, field), getfield_pullback
end

[willtebbutt]

Looks correct to me 🤷‍♂

[cossio]

There is a typo, name should be :field.

Shouldn't this also return zeros for the other fields (besides the requested field for which the gradient is 1)?

[willtebbutt]

Shouldn't this also return zeros for the other fields (besides the requested field for which the gradient is 1)?

Composite handles this lazily -- not specifying a field is essentially the same as setting it to Zero :)