fn unary_prec(op: &Op) -> u8Expand description
The precedence at which a prefix operator (Op with no second operand)
parses its operand, mirroring Parser::parse_prefix: -/+ at
PrefixPlusMinus, but ~ (and namespaced prefixes) at Other, so ~ a + b
parses as ~ (a + b). ~ binds looser than +/-/*.