Bigint.BigInt.modpow: def of bend-kit-bignum@0.1.0.0
Import: import bend-kit-bignum@0.1.0.0/bigint.bend as Bigint
Lines 452-458 of bend-kit-bignum@0.1.0.0/bigint.bend: https://jend.leeeet.dev/read.txt?path=bend-kit-bignum@0.1.0.0/bigint.bend&start_line=452&end_line=458

import Base

# b^e mod |m| in [0, |m|). None for m = 0 or e < 0.
def BigInt.modpow(b: BigInt, e: BigInt, m: BigInt) -> Maybe<&2, BigInt>:
  match b e m:
    case BigInt{sb, x} BigInt{se, y} BigInt{sm, Nil{}}:
      None{}
    case BigInt{sb, x} BigInt{se, y} BigInt{sm, z}:
      BigInt.modpow.go(se, sb, x, y, z)

Uses (4):
  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=bend-kit-bignum@0.1.0.0/bigint.bend&name=BigInt
  https://jend.leeeet.dev/definition.txt?path=bend-kit-bignum@0.1.0.0/bigint.bend&name=BigInt.modpow.go