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Description
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The Not keyword is
used in two different ways:
1. To
perform a logical or boolean 'Not' of a logical
value.If True, the value becomes False. If False,
the value becomes True.
2. To
perform a mathematical 'Not' of an integer in a
bitwise fashion. The result is a bitwise 'Not' of
the number - every bit value is reversed - 0 to 1
and 1 to 0.
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Notes
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If the boolean expression is calculated (as opposed
to being a Boolean variable), then brackets are
required to isolate it.
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Related commands
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And
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Boolean and or bitwise
and of two arguments
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Boolean
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Allows just True and
False values
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If
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Starts a conditional expression to determine
what to do next
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Or
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Boolean or or bitwise
or of two arguments
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Xor
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Boolean Xor or bitwise
Xor of two arguments
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Example code : Illustrate
both types of Not usage
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var
num1, num2 : Word;
begin
num1 :=
$2C; // Binary value : 0000 0000 0010
1100
//
Not'ed value : 1111 1111 1101 0011 =
$FFD3
// And
used to return a Boolean
value
if Not (num1 >
0)
then ShowMessage('num1 <= 0')
else ShowMessage('num1 > 0');
// And
used to perform a mathematical NOT
operation
num2 := Not num1;
//
Display the result
ShowMessage('Not $2C =
$'+IntToHex(num2,2));
end;
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Show full unit code
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num1 > 0
Not $2C = $FFD3
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