def unrecorded

bendtorch-core@0.1.0.0 · src/autograd/tensor_backward.bend:1307

import Base

1307# A refused sum drops the product, the newest entry, so the tape comes back
1308# as it was before the product was recorded.
1309def unrecorded(pair: Tape & Result<&2, &2, Error, Nat>) -> Tape & Result<&2, &2, Error, Nat>:
1310  (tape, result) = pair
1311  match result:
1312    case Fail{error}:
1313      (popped(tape), Fail{error})
1314    case Done{id}:
1315      (tape, Done{id})