BIT

• Source: https://www.freebasic.net/wiki/wikka.php?wakka=KeyPgBit
• Last revised: 2020-06-16

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Gets the state of an individual bit in an integer value.

Syntax

` #define Bit( value, bit_number ) (((value) and (Cast(TypeOf(value), 1) shl (bit_number))) <> 0)

`

Usage

` result = Bit( value, bit_number )

`

Parameters

value

The integer value.

bit_number

The index of the bit.

Return Value

Returns an Integer value of -1 if the bit is set, or 0 if the bit is cleared.

Description

This macro expands to an integer value indicating whether or not the bit specified by bit_number is set in the integer value. Behaves as (value And 1 Shl bit_number) <> 0.

The valid range of values for bit_number depends on the size, in bits, of Typeof(value), which is 0 (from the lowest bit) through Sizeof(value) * 8 - 1 (up to the highest bit). See Standard Datatype Limits for a table of the standard datatypes and their sizes.

For the bit_number values outside the valid range, the results of this macro are undefined.

Examples

start GeSHi

Print Bit(&B1000, 3)
Print Bit(4,2)
Print Bit(5,1)
Print Bit(&H8000000000000000ULL,63)

end GeSHi

will produce the output:

-1
-1
 0
-1

Dialect Differences

• Not available in the -lang qb dialect unless referenced with the alias __Bit.

Differences from QB

• New to FreeBASIC

See also

• Bitset
• Bitreset

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