Fix example code for unreachable! #19360
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The previous code was giving an incorrect result (not x/3).
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Thanks for the pull request, and welcome! The Rust team is excited to review your changes, and you should hear from @alexcrichton (or someone else) soon. |
| /// fn divide_by_three(x: u32) -> u32 { // one of the poorest implementations of x/3 | ||
| /// for i in std::iter::count(0_u32, 1) { | ||
| /// if 3*i < i { panic!("u32 overflow"); } | ||
| /// if x < 3*i { return i-1; } |
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<= 3*i should be sufficient (and more clear), no? Using checked_mul would also make more sense to me than the explicit panic guard.
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No, with <= 3*i, this gives:
0/3=0
1/3=1
2/3=1
3/3=1
4/3=2
5/3=2
6/3=2
bors
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Nov 28, 2014
The previous code was giving an incorrect result (not x/3). Also, this function does not work with signed integers. It now accepts `u32` instead of `i32`.
lnicola
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Apr 28, 2025
internal: Require Rust 1.85
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The previous code was giving an incorrect result (not x/3).
Also, this function does not work with signed integers. It now accepts
u32instead ofi32.