On 20.09.2017 23:13, nkm1 wrote:
Example of a good use:
void floodFill(dchar[][] data,dchar c,int i,int j) {
void dfs(int a, int b) {
Example of a good use:
void floodFill(dchar[][] data,dchar c,int i,int j) {
void dfs(int a, int b) {
if (a<0 || a >= data.length) return;
if (b<0 || b >= data[a].length) return;
if (data[a][b] == c) return;
data[a][b] = c;
foreach(i; 0 .. 4){
dfs(a + (i==0) - (i==1),
b + (i==2) - (i==3));
}
}
dfs(i, j);
}
I don't agree it's a good use.
Well, you can trust me that it is. ;)
Actually, that seems quite obfuscated to me.
It's actually straightforward. This C code is obfuscated:
#define C ,
#define S(X) "Fizz"X"Buzz"
int main(){
char j[]="00",*k=j+1,*g[]={k,S(C),S()};
while(':'-*j)
++*k>'9'&&++*j&&(1<:*g=j:>='0'),
puts(g[!((*j+*k)%3)|2*(3==*k%5)]);
return 0;
}
(And yet, you are probably able to guess what it does.)
Consider:
(I had considered that.)
foreach (point; [[1, 0], [-1, 0], [0, 1], [0, -1]]) {
dfs(a + point[0], b + point[1]);
}
void floodFill(dchar[][] data,dchar c,int i,int j) @nogc {
I.e., I'd possibly call this a bad use of array literals. ;)
(The fix is to initialize a static array of static arrays.)
Also, it's not really a point, rather, it's a delta.
Finds some random 10 programmers and ask them what's easier to understand...
Personally, I think it is a tie as both are obvious.
Also, in my experience (in C and C++) it is extremely rare for programmers to
use booleans in arithmetic. So even if in some situation you would have to
replace this thing with more verbose (i == 0 ? 1 : 0), it's no big deal.
I didn't say it was.
OTOH, booleans being numbers is a source of some bugs (just like other cases of weak typing). Not a ton of bugs, but the utility of implicit conversion to numbers is so unnoticeable that I'm sure it's just not worth it.
So am I, but I wasn't commenting on trade-offs, only the view that there
are no good uses.
