Negate ‘!’

The unary operator ‘!’ is used to perform a logical NOT operation on a boolean expression in JsonQL. It negates the boolean value of its operand.

Operator Priority: 100

Operator Operands

  • Operand 1:

    • Type: any valid JsonQL expression (including invalid path).

    • Description: Any valid JsonQL expression.

  • Operand 2:

    • Type: any valid JsonQL expression (including invalid path).

    • Description: Any valid JsonQL expression.

Evaluation Rules

The ! operator follows these evaluation rules:

  • !true: Returns false

  • !false: Returns true

  • Invalid paths: When the operand is an invalid path, the negation returns true

  • Null values: When the operand is null, the negation returns true

  • Non-boolean values: Any non-boolean value (such as integers, strings, etc.) is treated as “not false”, so the negation returns true

Note

The ! operator returns false only when applied to the boolean value true. All other values (including boolean false, invalid paths, null values, and non-boolean values) result in true when negated.

Examples

{
  "Comment_Operator_!_1": "(!invalid.path) is evaluated to true",
  "Operator_!_1": "$value(!invalid.path)",

  "Comment_Operator_!_2": "(!NullValue) is evaluated to true",
  "Operator_!_2": "$value(!NullValue)",

  "Comment_Operator_!_3": "(!Int1) is evaluated to true. Any value other than boolean false is evaluated to true",
  "Operator_!_3": "$value(!Int1)",

  "Operator_!_4": "$value(!(Int1 == 15) == false)",
  "Operator_!_5": "$value(!TrueValue == false)",
  "Operator_!_6": "$value(!FalseValue)",

  "Operator_!_7": "$value(Companies.Select(c => c.Employees.Where(e => !(e.Age > 40 || e.Salary > 100000))).First())"
}