def bump

bendtorch-core@0.1.0.0 · src/autograd/tensor_backward.bend:725

import Base
import bendtorch-core@0.1.0.0/src/shape/core.bend as Shape
import bendtorch-core@0.1.0.0/src/tensor/core.bend as Core
import bendtorch-core@0.1.0.0/src/autograd/gradient.bend as Gradient

725# Accumulates a contribution into the slot of node target, in a newest-first
726# list of count slots; same says whether the head is that node. A target the
727# list does not hold changes nothing.
728def bump(slots: List<&1, Gradient.Slot>, +count: Nat, +target: Nat, +shape: Shape.Shape, gradient: Core.Dynamic, same: Bool) ->
729  Result<&2, &1, Error, List<&1, Gradient.Slot>>:
730  match slots count same:
731    case Nil{} count same:
732      Done{Nil{}}
733    case Con{slot, rest} 0n same:
734      Done{slot <> rest}
735    case Con{slot, rest} 1n+below True{}:
736      placed(rest, Gradient.accumulate(shape, slot, gradient))
737    case Con{slot, rest} 1n+below False{}:
738      prepend(Gradient.Slot, slot, bump(rest, below, target, shape, gradient, at_head(below, target)))