Cli.osa_row: def of cli@0.2.0.0
Import: import cli@0.2.0.0/cli.bend as Cli
Lines 5692-5706 of cli@0.2.0.0/cli.bend: https://jend.leeeet.dev/read.txt?path=cli@0.2.0.0/cli.bend&start_line=5692&end_line=5706

import Base

# Row i of optimal string alignment for a[i]: up starts at d[i-1][j-1], up2
# at d[i-2][j-2], and left is d[i][j-1].
def osa_row(bs: String, bp: Maybe<&2, Char>, +a: Char,
    +ap: Maybe<&2, Char>, +up: List<&2, Nat>, +up2: List<&2, Nat>,
    left: Nat) -> List<&2, Nat>:
  match bs:
    case SNil{}: Nil{}
    case SCon{+b, tail}:
      +diag = head_nat(up)
      +rest = tail_nats(up)
      +edit = Nat.min(Nat.min((head_nat(rest) + 1n : Nat), (left + 1n : Nat)),
        Bool.pick(Nat, Char.is_eq(a, b), diag, (diag + 1n : Nat)))
      +best = Bool.pick(Nat, Bool.and(same_char(bp, a), same_char(ap, b)),
        Nat.min(edit, (head_nat(up2) + 1n : Nat)), edit)
      best <> osa_row(tail, Some{b}, a, ap, rest, tail_nats(up2), best)

Uses (13):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.and
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.pick
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Char
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Char.is_eq
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Maybe
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.add
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.min
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=String
  https://jend.leeeet.dev/definition.txt?path=cli@0.2.0.0/cli.bend&name=head_nat
  https://jend.leeeet.dev/definition.txt?path=cli@0.2.0.0/cli.bend&name=same_char
  https://jend.leeeet.dev/definition.txt?path=cli@0.2.0.0/cli.bend&name=tail_nats