Not (')

Details

The Not operator inverts the truth value of the boolean operand. If the operand is TRUE (1), Not gives it a value of FALSE (0). If the operand is FALSE (0), Not gives it a value of TRUE (1).

Examples

For example, the following statements produce a result of FALSE (0):

  SET x=0
  WRITE x

While the following statements produces a result of TRUE (1).

  SET x=0
  WRITE 'x

The Not operator combined with a comparison operator inverts the sense of the comparison. For example, the following statement displays a result of FALSE (0):

  WRITE 3>5

But, the following statement displays a result of TRUE (1):

  WRITE 3'>5