Ops.keys: def of near-v-framework@0.4.0.0
Import: import near-v-framework@0.4.0.0/general/rose/ops.bend as Ops
Lines 9-17 of near-v-framework@0.4.0.0/general/rose/ops.bend: https://jend.leeeet.dev/read.txt?path=near-v-framework@0.4.0.0/general/rose/ops.bend&start_line=9&end_line=17

import Base
import near-v-framework@0.4.0.0/general/rose/type.bend as R

# Every key in a forest, each tree's own key before its children's.
def keys(-N: Data, rs: List<&2, R.Rose<N>>) -> List<&2, String>:
  match rs:
    case []:
      []
    case r <> rest:
      match r:
        case R.Rose{k, _, kids}:
          k <> List.append(&2, String, keys(N, kids), keys(N, rest))

Uses (4):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List.append
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String
  https://jend.leeeet.dev/definition.txt?path=near-v-framework@0.4.0.0/general/rose/type.bend&name=Rose