Safe Shifts

It is safe to shift (<<, >>) a value of type T where `β = sizeof(T) * 8 (with SafeUnsigned value

• by 0 bits, in which case the result is the value unchanged
• by bitsof(T) bits, in which case the result is zero(T)
• by -bitsof(T) bits, in which case the result is zero(T)
• by ⦃1, .., bitsof(T)-1⦄
  • the result is strictly less than any nonzero value given
  • the result, given a zero value remains zero
• by ⦃-1, .., -(bitsof(T)-1)⦄
  • the result is strictly greater than any nonzero value given
  • the result, given a zero value remains zero

of type T by 0 bits (unchanged) or by ±β bits where β ∈ ⦃0, 1, .., bitsof(T)⦄.

An OverflowError occurs when there is an attempt to shift a value of safe type T by a magnitude greater than ±bitsof(T).