rust-guide::13.3 Generating a secret number

[anmej]

cc @steveklabnik

This part is somewhat confusing:
let secret_number = (rand::random::<int>() % 100i) + 1i;

My suggestion is: either mention that rand::random::<int>() samples the whole range of int and you use modulo to narrow the range. Or use the std::rand::distributions::Range function. This way you also don't get modulo bias.

[sinistersnare]

cc @steveklabnik

(If you want to mention someone, use @<THEIR_USERNAME>)

[anmej]

Done, thanks.

[huonw]

Or use the 'std::rand::distributions::Range' function. This way you also don't get modulo bias.

I pulled this up in the original review: #15729 (comment). As you can see the modulo bias is miniscule (even on 32-bit platforms it is only billionths).

[anmej]

The introduction of modulo bias is not the main issue. The issue is that I, as a newbie, got confused by the %100 trick, so maybe it needs some more explanation.

[treeman]

I agree. std::rand::distributions::Range should also be the recommended way to generate a random number in a range. If it will be expanded on later in the guide, that's fine, but then some more explanation here could be nice.

@anmej If you surround your code with backticks, like let a = 2; then you'll get code sytax let a = 2;