I have implemented in CTFE, what I'd like asserts to look like: http://dpaste.1azy.net/2ec082c0
It prints at runtime: "x > y && x < 10" (x must be a digit and larger than y) failed with x: 2, y: 3 ---------------- <stack trace> When you write a contract like this: void foo(uint x, uint y) in { mixin(q{ x > y && x < 10 }.holds ("x must be a digit and larger than y")); } body { … } -- Marco