Defs.run_len: def of lawful-bytes@0.1.1.0
Import: import lawful-bytes@0.1.1.0/defs.bend as Defs
Lines 57-63 of lawful-bytes@0.1.1.0/defs.bend: https://jend.leeeet.dev/read.txt?path=lawful-bytes@0.1.1.0/defs.bend&start_line=57&end_line=63

import Base

# How many leading elements are not c.
def run_len(xs: List<&2, U32>, +c: U32) -> Nat:
  match xs:
    case Nil{}:
      0n
    case Con{+x, t}:
      Bool.pick(Nat, U32.is_eq(x, c), 0n, Nat.add(1n, run_len(t, c)))

Uses (6):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool.pick
  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=Nat.add
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32.is_eq