Fixbytes.fle4: def of bend-collections-laws-math@1.0.0.0
Import: import bend-collections-laws-math@1.0.0.0/proofs/math/typed/fixbytes.bend as Fixbytes
Lines 159-165 of bend-collections-laws-math@1.0.0.0/proofs/math/typed/fixbytes.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/typed/fixbytes.bend&start_line=159&end_line=165

import Base
import bend-collections-laws-math@1.0.0.0/spec/math/generic.bend as SG
import bend-collections-laws-math@1.0.0.0/spec/math/fixed.bend as SF
import bend-collections-laws-math@1.0.0.0/src/math/fixed.bend as F

# the list cases: exactly four bytes, or None on both sides
def fle4(+b0: U32, +b1: U32, +b2: U32, +b3: U32, t: List<&2, U32>) -> {SF.mval(~U32, ~SG.u32_val, F.u32_from_bytes_le(Con{b0, Con{b1, Con{b2, Con{b3, t}}}})) == SF.from_le(4n, SF.nats(Con{b0, Con{b1, Con{b2, Con{b3, t}}}})) : Maybe<&2, Nat>}:
  match t:
    case Nil{}:
      from4_ok(b0, b1, b2, b3)
    case Con{+b4, t5}:
      {==}

Uses (10):
  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=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=U32
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/typed/fixbytes.bend&name=from4_ok
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/spec/math/fixed.bend&name=from_le
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/spec/math/fixed.bend&name=mval
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/spec/math/fixed.bend&name=nats
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/spec/math/generic.bend&name=u32_val
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/src/math/fixed.bend&name=u32_from_bytes_le