Surprisingly, the sizeof operator applies to prefix expressions, too, except casting. So sizeof !x works, but sizeof (int)x doesn't, despite ! and casting havin

Surprisingly, the sizeof operator applies to prefix expressions, too, except casting. So sizeof !x works, but sizeof (int)x doesn't, despite ! and casting having the same precedence. The presence of (int) sort of promotes sizeof from "operator that applies to expressions" to "function that takes a type". I think this is a side effect of reusing the same keyword for two syntactically different constructs.