Empty.kept: def of bolt@1.27.0.0
Import: import bolt@1.27.0.0/src/rules/suspicious/empty.bend as Empty
Lines 201-217 of bolt@1.27.0.0/src/rules/suspicious/empty.bend: https://jend.leeeet.dev/read.txt?path=bolt@1.27.0.0/src/rules/suspicious/empty.bend&start_line=201&end_line=217

import Base
import bolt@1.27.0.0/src/syntax/lex.bend as Lex

# is x read among the tokens before the bracket that closes the group they
# sit in? found carries whether the last token read was x, live whether that
# bracket is still ahead
def kept(toks: List<&2, Lex.Tok>, +xx: String, +dd: Nat, found: Bool, live: Bool) -> Bool:
  match toks:
    case Nil{}:
      found
    case Con{Lex.Tok{+k, +t, l, c}, rest}:
      match found:
        case True{}:
          True{}
        case False{}:
          match live:
            case False{}:
              False{}
            case True{}:
              kept(rest, xx, close.depth(k, dd), same(k, t, xx), Bool.not(close.here(k, dd)))

Uses (9):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.not
  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=String
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/rules/suspicious/empty.bend&name=close.depth
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/rules/suspicious/empty.bend&name=close.here
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/rules/suspicious/empty.bend&name=same
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/syntax/lex.bend&name=Tok