Sgd.descend_at: def of bendtorch-core@0.1.0.0
Import: import bendtorch-core@0.1.0.0/src/autograd/sgd.bend as Sgd
Lines 127-138 of bendtorch-core@0.1.0.0/src/autograd/sgd.bend: https://jend.leeeet.dev/read.txt?path=bendtorch-core@0.1.0.0/src/autograd/sgd.bend&start_line=127&end_line=138

import Base
import bendtorch-core@0.1.0.0/src/autograd/tensor_backward.bend as Backward

# Updates entry id of a newest-first list of count entries and keeps every
# other entry.
def descend_at(+lr: F32, entries: List<&1, Backward.Entry>, +count: Nat, +id: Nat, same: Bool) -> Walked():
  match entries count same:
    case Nil{} count same:
      (Nil{}, Fail{UnknownNode{}})
    case Con{entry, rest} 0n same:
      (entry <> rest, Fail{UnknownNode{}})
    case Con{entry, rest} 1n+below True{}:
      placed(rest, descend(lr, entry))
    case Con{entry, rest} 1n+below False{}:
      kept(entry, descend_at(lr, rest, below, id, Backward.at_head(below, id)))

Uses (13):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=F32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Result
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Sigma
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/autograd/sgd.bend&name=Error
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/autograd/sgd.bend&name=Walked
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/autograd/sgd.bend&name=descend
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/autograd/sgd.bend&name=kept
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/autograd/sgd.bend&name=placed
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/autograd/tensor_backward.bend&name=Entry
  https://jend.leeeet.dev/definition.txt?path=bendtorch-core@0.1.0.0/src/autograd/tensor_backward.bend&name=at_head