I have some rather odd behavior in my D program that I've narrowed down to this:
import std.algorithm;
import std.stdio;
import std.traits;
enum E { a, b, c };
struct S { E e; };
void main()
{
immutable(S)[] source = [ S(E.a), S(E.a), S(E.b) ];
foreach (e; EnumMembers!E)
{
size_t c = count!(x => x.e == e)(source);
writeln(e, " -> ", c);
}
}
I would expect the output of this program to be something along the lines of:
a -> 2
b -> 1
c -> 0
But the actual result is:
a -> 2
b -> 2
c -> 2
Curiously, changing the for loop to foreach (e; [ E.a, E.b, E.c ]) produces my
expected output. Using foreach (e; [ EnumMembers!E ]) also produces my
expected result, so clearly my use of the range from EnumMemebers is the
problem here...I just don't know why.
By moving the count call to a separate function:
size_t counte(Range)(E e, Range src)
{
return count!(x => x.e == e)(src);
}
and changing c's initialization to size_t c = counte(e, source);, the program
works as I would expect.
I am clearly doing something wrong, but I have no idea what and would
appreciate some insight.
My compiler is DMD64 D Compiler v2.059 on Linux.
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