This section describes functions and operators for examining and manipulating bit strings, that is values of the types bit and bit varying. (While only type bit is mentioned in these tables, values of type bit varying can be used interchangeably.) Bit strings support the usual comparison operators shown in Table 9.1, as well as the operators shown in Table 9.14.
Table 9.14. Bit String Operators
Operator Description Example(s) |
---|
bit Concatenation
|
bit Bitwise AND (inputs must be of equal length)
|
bit Bitwise OR (inputs must be of equal length)
|
bit Bitwise exclusive OR (inputs must be of equal length)
|
Bitwise NOT
|
bit Bitwise shift left (string length is preserved)
|
bit Bitwise shift right (string length is preserved)
|
Some of the functions available for binary strings are also available for bit strings, as shown in Table 9.15.
Table 9.15. Bit String Functions
In addition, it is possible to cast integral values to and from type
bit.
Casting an integer to bit(n) copies the rightmost
n
bits. Casting an integer to a bit string width wider
than the integer itself will sign-extend on the left.
Some examples:
44::bit(10) 0000101100 44::bit(3) 100 cast(-44 as bit(12)) 111111010100 '1110'::bit(4)::integer 14
Note that casting to just “bit” means casting to
bit(1)
, and so will deliver only the least significant
bit of the integer.