What's interesting is that other languages have since adopted CTFE, but they missed the point and did it wrong. The usual mistake is to add a keyword necessary

What's interesting is that other languages have since adopted CTFE, but they missed the point and did it wrong. The usual mistake is to add a keyword necessary to trigger it. D triggers it when an expression appears where a "const-expression" appears in the grammar. I.e: int x = f(); // f() is run at run time enum y = f(); // f() is run at compile time