CLHS: Accessor BIT, SBIT

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Accessor BIT, SBIT

Syntax:

bit bit-array `&rest` subscripts => bit

sbit bit-array `&rest` subscripts => bit

`(setf (`bit bit-array `&rest` subscripts`)` new-bit`)`

`(setf (`sbit bit-array `&rest` subscripts`)` new-bit`)`

Arguments and Values:

bit-array---for bit, a bit array; for sbit, a simple bit array.

subscripts---a list of valid array indices for the bit-array.

bit---a bit.

Description:

bit and sbit access the bit-array element specified by subscripts.

These functions ignore the fill pointer when accessing elements.

Examples:

     (bit (setq ba (make-array 8
                                :element-type 'bit
                                :initial-element 1))
           3) =>  1
     (setf (bit ba 3) 0) =>  0
     (bit ba 3) =>  0
     (sbit ba 5) =>  1
     (setf (sbit ba 5) 1) =>  1
     (sbit ba 5) =>  1

Affected By: None.

Exceptional Situations: None.

See Also:

aref, Section 3.2.1 (Compiler Terminology)

Notes:

bit and sbit are like aref except that they require arrays to be a bit array and a simple bit array, respectively.

bit and sbit, unlike char and schar, allow the first argument to be an array of any rank.

The following X3J13 cleanup issue, not part of the specification, applies to this section:

- CONSTANT-MODIFICATION:DISALLOW

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