F# - Bitwise Operators


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Bitwise operators work on bits and perform bit-by-bit operation. The truth tables for &&& (bitwise AND), ||| (bitwise OR), and ^^^ (bitwise exclusive OR) are as follows −

p q p &&& q p ||| q p ^^^ q
0 0 0 0 0
0 1 0 1 1
1 1 1 1 0
1 0 0 1 1

Assume if A = 60; and B = 13; now in binary format they will be as follows −

A = 0011 1100

B = 0000 1101

-----------------

A&&&B = 0000 1100

A|||B = 0011 1101

A^^^B = 0011 0001

~~~A = 1100 0011

The Bitwise operators supported by F# language are listed in the following table. Assume variable A holds 60 and variable B holds 13, then −

Operator Description Example
&&& Binary AND Operator copies a bit to the result if it exists in both operands. (A &&& B) will give 12, which is 0000 1100
||| Binary OR Operator copies a bit if it exists in either operand. (A ||| B) will give 61, which is 0011 1101
^^^ Binary XOR Operator copies the bit if it is set in one operand but not both. (A ^^^ B) will give 49, which is 0011 0001
~~~ Binary Ones Complement Operator is unary and has the effect of 'flipping' bits. (~~~A) will give -61, which is 1100 0011 in 2's complement form.
<<< Binary Left Shift Operator. The left operands value is moved left by the number of bits specified by the right operand. A <<< 2 will give 240 which is 1111 0000
>>> Binary Right Shift Operator. The left operands value is moved right by the number of bits specified by the right operand. A >>> 2 will give 15 which is 0000 1111

Example

let a : int32 = 60 // 60 = 0011 1100
let b : int32 = 13 // 13 = 0000 1101
let mutable c : int32 = 0

c <- a &&& b // 12 = 0000 1100
printfn "Line 1 - Value of c is %d" c

c <- a ||| b // 61 = 0011 1101
printfn "Line 2 - Value of c is %d" c

c <- a ^^^ b // 49 = 0011 0001
printfn "Line 3 - Value of c is %d" c

c <- ~~~a // -61 = 1100 0011
printfn "Line 4 - Value of c is %d" c

c <- a <<< 2 // 240 = 1111 0000
printfn "Line 5 - Value of c is %d" c

c <- a >>> 2 // 15 = 0000 1111
printfn "Line 6 - Value of c is %d" c

When you compile and execute the program, it yields the following output −

Line 1 - Value of c is 12
Line 2 - Value of c is 61
Line 3 - Value of c is 49
Line 4 - Value of c is 49
Line 5 - Value of c is 240
Line 6 - Value of c is 15
fsharp_operators.htm
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