F64bits.andw: def of bend-collections-laws-math@1.0.0.0
Import: import bend-collections-laws-math@1.0.0.0/proofs/math/typed/f64bits.bend as F64bits
Lines 38-46 of bend-collections-laws-math@1.0.0.0/proofs/math/typed/f64bits.bend: https://jend.leeeet.dev/read.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/typed/f64bits.bend&start_line=38&end_line=46

import Base
import bend-collections-laws-math@1.0.0.0/spec/lib/common.bend as C
import bend-collections-laws-math@1.0.0.0/proofs/lib/logic.bend as L
import bend-collections-laws-math@1.0.0.0/proofs/lib/lemmas/spec/numeric.bend as S
import bend-collections-laws-math@1.0.0.0/proofs/lib/u32.bend as U
import bend-collections-laws-math@1.0.0.0/proofs/lib/word.bend as WD
import bend-collections-laws-math@1.0.0.0/proofs/math/typed/width.bend as WW

# the low k bits of a word
def andw(+n: Nat, +k: Nat, +w: Word(n)) -> {S.unsigned(n, Word.and(n, w, WD.mask(n, k))) == C.low(k, S.unsigned(n, w)) : Nat}:
  +a = S.unsigned(n, Word.and(n, w, WD.mask(n, k)))
  +hp = WD.hi_part(n, k, w)
  +e1 = WD.mask_split(n, k, w)
  +e2 = Equal.trans(Nat, S.unsigned(n, w), Nat.add(a, S.scale_binary(k, hp)), Nat.add(a, C.shift(k, hp)), e1, Equal.cong(Nat, Nat, z => Nat.add(a, z), S.scale_binary(k, hp), C.shift(k, hp), sb(k, hp)))
  +hl = WD.mask_lt(n, k, 1n, {==}, w)
  +hl2 = L.subst(Nat, z => {Nat.is_lt(a, z) == True{} : Bool}, S.scale_binary(k, 1n), C.pow2(k), Equal.sym(Nat, C.pow2(k), S.scale_binary(k, 1n), U.pow2_scale(k)), hl)
  Equal.sym(Nat, C.low(k, S.unsigned(n, w)), a, Equal.trans(Nat, C.low(k, S.unsigned(n, w)), C.low(k, Nat.add(a, C.shift(k, hp))), a, Equal.cong(Nat, Nat, z => C.low(k, z), S.unsigned(n, w), Nat.add(a, C.shift(k, hp)), e2), WW.low_uniq(k, a, hp, hl2)))

Uses (22):
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Bool
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.cong
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.sym
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Equal.trans
  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=Nat.is_lt
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Word
  https://jend.leeeet.dev/definition.txt?path=Base/base.bend&name=Word.and
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/lemmas/spec/numeric.bend&name=scale_binary
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/lemmas/spec/numeric.bend&name=unsigned
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/logic.bend&name=subst
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/u32.bend&name=pow2_scale
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/word.bend&name=hi_part
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/word.bend&name=mask
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/word.bend&name=mask_lt
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/lib/word.bend&name=mask_split
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/typed/f64bits.bend&name=sb
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/proofs/math/typed/width.bend&name=low_uniq
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/spec/lib/common.bend&name=low
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/spec/lib/common.bend&name=pow2
  https://jend.leeeet.dev/definition.txt?path=bend-collections-laws-math@1.0.0.0/spec/lib/common.bend&name=shift