LAWS.byte_pack4: law of lawful-words@0.1.0.0
Import: import lawful-words@0.1.0.0/LAWS.bend as LAWS
Lines 360-373 of lawful-words@0.1.0.0/LAWS.bend: https://jend.leeeet.dev/read.txt?path=lawful-words@0.1.0.0/LAWS.bend&start_line=360&end_line=373

import Base
import lawful-words@0.1.0.0/defs.bend as D

# Unpacking a packed word gives its bytes back. j is any index below 4 (in
# code it is i & 3, not a literal).
law byte_pack4:
  for b0: U32
  for b1: U32
  for b2: U32
  for b3: U32
  for j: Nat
  for h0: {U32.is_lt(b0, 256) == True{} : Bool}
  for h1: {U32.is_lt(b1, 256) == True{} : Bool}
  for h2: {U32.is_lt(b2, 256) == True{} : Bool}
  for h3: {U32.is_lt(b3, 256) == True{} : Bool}
  for hj: {Nat.is_lt(j, 4n) == True{} : Bool}
  {D.byte(D.pack4(b0, b1, b2, b3), j) == D.nth4(j, b0, b1, b2, b3) : U32}

Uses (9):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Nat.is_lt
  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_lt
  https://jend.leeeet.dev/definition.txt?path=lawful-words@0.1.0.0/defs.bend&name=byte
  https://jend.leeeet.dev/definition.txt?path=lawful-words@0.1.0.0/defs.bend&name=nth4
  https://jend.leeeet.dev/definition.txt?path=lawful-words@0.1.0.0/defs.bend&name=pack4
  https://jend.leeeet.dev/definition.txt?path=lawful-words@0.1.0.0/proof_bytes.bend&name=byte_pack4