List.foldl: def of Base
Import: import Base
Lines 1070-1077 of Base/base.bend: https://jend.leeeet.dev/read.txt?path=Base/base.bend&start_line=1070&end_line=1077

import Base

def List.foldl(
  ~a: Quant, ~A: Kind(a), ~B: Type, ~f: B -> A -> B, xs: List<a, A>, acc: B
) -> B:
  match xs:
    case Nil{}:
      acc
    case h <> t:
      List.foldl(~a, ~A, ~B, ~f, t, f(acc, h))

Uses (1):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=List