Python cryptography, Rust, and Gentoo

> While you can say: lim x→0 n/x = inf, it does not follow that n/0 = inf.

No, you can't say that. For n∈ℝ⁺, lim (x⭢0)⁺ (n/x) = ∞, but lim (x⭢0)⁻ (n/0) = -∞, so lim x⭢0 (n/0) does not exist. [For n∈ℝ⁻, lim (x⭢0)⁺ (n/x) = -∞ and lim (x⭢0)⁻ (n/x) = ∞, so lim (x⭢0) does not exist either; but for n∈{0}, lim (x⭢0)⁺ (n/x) = 0 and lim (x⭢0)⁻ (n/x) = 0, and so lim (x⭢0) (n/x) = 0].

> But isn't that what the MATHS MEANS? It doesn't follow that x will *reach* 0, but if it does, then n/x *must* equal infinity. (Quite often, x=0 is illegal in the problem domain.)

No, the maths says that the domain of the divisor does not include zero; that the closer to zero a positive divisor gets, the closer to positive infinity the value gets; and that the closer to zero a negative divisor gets, the closer to negative infinity the value gets.