Here's a simplified example of what I want to achieve.
I first create funs, an array of two delegates.
I want funs[0] to always return 0 and funs[1] to always return 1.
By assigning the constants directly (see the code below), I
achieve exactly that.
Now, I want to use a loop to assign the values, and this is where
things stop working.
My first try is guns, populated with `foreach (i; 0..2) guns ~=
() => i;`.
But both guns[0] and guns[1] return 1.
I tried to circumvent that by populating another array, huns,
with functions returning immutable copies of the loop variable,
but the effect was the same.
import std.stdio;
void main () {
int delegate () [] funs;
funs ~= () => 0;
funs ~= () => 1;
foreach (i; 0..2) writeln (funs[i] ()); // 0 and 1 as expected
int delegate () [] guns;
foreach (i; 0..2) guns ~= () => i;
foreach (i; 0..2) writeln (guns[i] ()); // 1 and 1, why?
int delegate () [] huns;
foreach (i; 0..2) {
immutable int j = i;
huns ~= () => j;
}
foreach (i; 0..2) writeln (huns[i] ()); // 1 and 1, why?
}
In my real use case, the delegates actually get stored in
different structs or classes instead of a single array, and
instead of returning 0 and 1, they call another function with
argument 0 and 1, respectively.
Also, the number of delegates to create is known only at runtime.
However, I believe that won't be a problem once I grasp how to do
this basic example.
So, why do delegates of guns[] and huns[] all return 1, and how
to correctly reproduce the behavior of funs[] while populating it
in a loop?
Ivan Kazmenko.