| ¬ 8 ≤ # bitsand(bits, int2bits(j)), int2bits(i) = bits0 + bits, # bits = 8, j < 0, # int2bits(j) < 8 ⊦ bitsand(bits, int2bits(j)) = [], lastn(8, fillsgn(8, bits0 + bitsand(bits, int2bits(j)))) = lastn(8, fillsgn(8, bitsand(bits, int2bits(j)))) |
# bits = 8, int2bits(i) = bits0 + bits, # bitsand(bits, int2bits(j)) < 8, # int2bits(j) < 8, j < 0 ⊦ lastn(8, fillsgn(8, bits0 + bitsand(bits, int2bits(j)))) = lastn(8, bitsand(bits, int2bits(j)).first ' + fillsgn(7, bitsand(bits, int2bits(j)))), bitsand(bits, int2bits(j)) = []
Used simplifier rules: ⊦ m < n ∧ n = n0 → m < n0; (forward)%⊦ bits ≠ [] ∧ # bits < n → fillsgn(n, bits) = bits.first ' + fillsgn(n -1, bits);% ⊦ ¬ m ≤ n ↔ n < m;