Thunk.lams: def of bolt@1.27.0.0
Import: import bolt@1.27.0.0/src/rules/suspicious/thunk.bend as Thunk
Lines 130-141 of bolt@1.27.0.0/src/rules/suspicious/thunk.bend: https://jend.leeeet.dev/read.txt?path=bolt@1.27.0.0/src/rules/suspicious/thunk.bend&start_line=130&end_line=141

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

# how many arguments of a group's kids, from here on, hold a `=>` leaf among
# their own nodes; seen: the argument under way does
def lams(nn: Tree.Node, +seen: Bool) -> Nat:
  match nn:
    case Tree.NCons{Tree.Leaf{Lex.Tok{k, t, _l, _c}}, rest}:
      +comma = Lex.is_comma(k)
      Nat.add(Bool.pick(Nat, Bool.and(comma, seen), 1n, 0n),
        lams(rest, Bool.and(Bool.not(comma), Bool.or(seen, String.eq(t, "=>")))))
    case Tree.NCons{_h, rest}:
      lams(rest, seen)
    case _other:
      Bool.pick(Nat, seen, 1n, 0n)

Uses (11):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  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.not
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.or
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.pick
  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=String.eq
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/syntax/lex.bend&name=Tok
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/syntax/lex.bend&name=is_comma
  https://jend.leeeet.dev/definition.txt?path=bolt@1.27.0.0/src/syntax/tree.bend&name=Node