Below is the list of unary operators:
"+". Unary plus is predefined for all numeric types. The result of using unary plus for a numeric type is an operand value.
"-". Unary minus is predefined for all numeric types. The result of using unary operator is calculated by subtracting operand value from zero.
Not. The NOT unary operator is predefined for operands having the logical data type. The result is operand negation.
Unary operators have only one operand. Unary operators are calculated in the first place in expressions.
See also:
Fore Language Guide | Arithmetic Operators | Logical Operators