AND
Result = Expression AND Expression
Depending on the expression, the AND operation can be either a logical AND or a numerical AND.
In case of two boolean expressions, a logical AND operation is performed. In case of two integer numbers, a numerical AND operation is performed.
Strings and objects are automatically converted to booleans.
A null string or a null object is converted to
FALSE, other values are converted to
TRUE.
Sinds 3.17
If one of the operands is a floating value, an error is raised.
Before Gambas 3.17, the floating point values were silently converted to Boolean, leading to a useless result.
The logical AND operator takes two boolean expressions and returns a true or false value. The results returned by this operator is shown in the following table:
|
A
|
B
|
A AND B
|
|---|
|
FALSE
|
FALSE
|
FALSE
|
|
FALSE
|
TRUE
|
FALSE
|
|
TRUE
|
FALSE
|
FALSE
|
|
TRUE
|
TRUE
|
TRUE
|
The numerical AND operator takes two integer values and returns an integer value. Each corresponding bit of the specified values are combined according to the following table:
|
A
|
B
|
A AND B
|
|---|
|
0
|
0
|
0
|
|
0
|
1
|
0
|
|
1
|
0
|
0
|
|
1
|
1
|
1
|
The numerical AND operator can be used to test the bit pattern of a number. It can also be used to mask out selected bits of a number. The following table gives some examples of how the AND operator works on two integer numbers.
|
Expression
|
Explanation
|
|---|
|
10 And 20 = 0
|
10 = binary 01010
20 = binary 10100
Hence 10 And 20 = 0
|
|
10 And -20 = 8
|
10 = binary 00000000000000000000000000001010
-20 = binary 11111111111111111111111111101100
Hence 10 And -20 = 8 (binary 1000)
|
|
20 And -20 = 4
|
20 = binary 00000000000000000000000000010100
-20 = binary 11111111111111111111111111101100
Hence 20 And -20 = 4 (binary 100)
|
Examples
Print True And False
Print True And True
Print 7, Bin(7, 16)
Print 11, Bin(11, 16)
Print 7 And 11, Bin(7 And 11, 16)
7 0000000000000111
11 0000000000001011
3 0000000000000011
Dim A, B As Boolean
A = 10 < 20
B = 20 > 30
If A And B Then
Print "Both A and B are TRUE"
Else
Print "Either A or B or both are FALSE"
Endif
Either A or B or both are FALSE
See also