On 12/13/2012 2:40 AM, bearophile wrote:
Walter Bright:
void main() {
int[5] x;
x[$] = 1;
enum size_t n = 2;
x[$ + n] = 2;
}
The compiler does that already.
I am compiling that little program with
dmd -w test.d
And I see no compilation errors.
Well, it should for those cases.
See also here, it gives a run-time error:
http://dpaste.dzfl.pl/a62a10aa
void main() {
int[] x = new int[5];
x[$] = 1; // easy
x[x.length] = 1; // idem
enum size_t n = 2;
x[$ + n] = 2; // not too much hard if n is unsigned
x[x.length + n] = 2; // idem
}
I just don't see the point in adding flow analysis for that,
I think that doesn't require flow analysis.
Yeah, it does, unless you care to put in the compiler a long list of special
cases. For example, what about $+$, n+$, $+$-$+1, $<<n, etc.? These sort of turn
into whack-a-mole games.
and it'll ding you at runtime anyway.
This thread is about spotting mistakes at compile-time, that is one of the main
advantages of having a static typing in the first place.
Since the bug is caught anyway, such is an extremely low priority because it's
got such a low payoff.
