I mean i < 10 isn’t wrong as such, it’s just good practice to always use <= because in the INT_MAX case you have to and everything should be regular because principle of least astonishment: That 10 might become a #define FOO 10, that then might become #define FOO INT_MAX, each of those changes look valid in isolation but if there’s only a single i < FOO in your codebase you introduced a bug by spooky action at a distance. (overflow on int is undefined behaviour in C, in case anyone is wondering what the bug is).
…never believe anyone who says “C is a simple language”. Their code is shoddy and full of bugs and they should be forced to write Rust for their own good.
But your case is wrong anyways because i <= INT_MAX will always be true, by definition. By your argument < is actually better because it is consistent from < 0 to iterate 0 times to < INT_MAX to iterate the maximum number of times. INT_MAX + 1 is the problem, not < which is the standard to write for loops and the standard for a reason.
You’re right, that’s what I get for not having written a line of C in what 15 years. Bonus challenge: write foriini32::MIN..=i32::MAX in C, that is, iterate over the whole range, start and end inclusive.
(I guess the ..= might be where my confusion came from because Rust’s .. is end-exclusive and thus like <, but also not what you want because i32::MAX + 1 panics).
Would you be bold enough to write if (i++ == INT_MAX) break? The result of the increment is never used, but an increment is being done, at least syntactically, and it overflows, at least theoretically, so maybe (I’m not 100% sure) the compiler could be allowed to break out into song because undefined behaviour allows anything to happen.
I mean
i < 10
isn’t wrong as such, it’s just good practice to always use<=
because in theINT_MAX
case you have to and everything should be regular because principle of least astonishment: That10
might become a#define FOO 10
, that then might become#define FOO INT_MAX
, each of those changes look valid in isolation but if there’s only a singlei < FOO
in your codebase you introduced a bug by spooky action at a distance. (overflow on int is undefined behaviour in C, in case anyone is wondering what the bug is).…never believe anyone who says “C is a simple language”. Their code is shoddy and full of bugs and they should be forced to write Rust for their own good.
But your case is wrong anyways because
i <= INT_MAX
will always be true, by definition. By your argument<
is actually better because it is consistent from< 0
to iterate 0 times to< INT_MAX
to iterate the maximum number of times.INT_MAX + 1
is the problem, not<
which is the standard to write for loops and the standard for a reason.You’re right, that’s what I get for not having written a line of C in what 15 years. Bonus challenge: write
for i in i32::MIN..=i32::MAX
in C, that is, iterate over the whole range, start and end inclusive.(I guess the
..=
might be where my confusion came from because Rust’s..
is end-exclusive and thus like<
, but also not what you want becausei32::MAX + 1
panics).for (int i = INT_MIN; ; i++) { ... if (i == INT_MAX) break;}
Would you be bold enough to write
if (i++ == INT_MAX) break
? The result of the increment is never used, but an increment is being done, at least syntactically, and it overflows, at least theoretically, so maybe (I’m not 100% sure) the compiler could be allowed to break out into song because undefined behaviour allows anything to happen.