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Boolean                  Logical Values (TRUE, FALSE)            Ordinal Type

    The data type Boolean represents logical values that are either TRUE
    or FALSE. Standard Pascal defines Boolean as an enumerated type:

         type
           Boolean         = (False,True);

    Thus, Ord(False) = 0, Ord(True) = 1, and False < True.

    Boolean values, and particularly Boolean expressions, are important
    because of their use in IF/THEN/ELSE statements, WHILE loops, and
    REPEAT loops. The most common Boolean expression are those involving
    relational operators: =, <>, <, >, <=, and >=. Standard Pascal also
    has three Boolean operators--NOT, AND, OR--which combine Boolean
    values and yield a Boolean result.

    Boolean variables in Turbo Pascal occupy one byte. This is true even
    if you declare a PACKED ARRAY OF Boolean or a PACKED RECORD with
    Boolean fields. Turbo Pascal also introduces an additional Boolean
    operator, XOR (exclusive OR).

  -------------------------------- Example ---------------------------------

           var
             Iota,Able,Fred : Boolean;

           begin
             Iota := True;          { Iota gets True }
             Able := (3 >= 5);      { Able gets False }
             Fred := Iota or Able;  { Fred gets True }
           end.

See Also: and or xor not enumerated packed record array
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