> Usually a ~ signifies a bitwise-NOT operation*. Only in expression context. C doesn't assign any meaning to ~ in type definition context, nor does it have an

> Usually a ~ signifies a bitwise-NOT operation*. Only in expression context. C doesn't assign any meaning to ~ in type definition context, nor does it have an existing way to represent the concept of "any type reducible to X". Since it doesn't diverge from C in either syntactic or semantic meanings when considering context, I don't see this being an issue in practice. Any potential confusion argument you can lay onto ~ could also be used against |, but I don't see any mention of that being a problem. I can't "disagree" with your reaction -- that would be silly even if I wanted to -- but I claim that you would likely stop suffering from increased mental effort as you read and write this syntax over time.