Bug 8614 – Cannot change the iteration index during CTFE

During runtime execution of a foreach loop, you can change the index. This doesn't work at compile-time and gives a different result when foo is called through CTFE or at runtime: import std.stdio; int[] foo(int[] data) { foreach (i, ref x; data) { x++; i++; } return data; } void main() { // Compile-time enum result1 = foo([10, 20, 30, 40]); assert(result1 == [11, 21, 31, 41]); // Runtime auto result2 = foo([10, 20, 30, 40]); assert(result2 == [11, 20, 31, 40]); }

*** This issue has been marked as a duplicate of issue 8498 ***