CLHS: Function LDB-TEST

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Function LDB-TEST

Syntax:

ldb-test bytespec integer => generalized-boolean

Arguments and Values:

bytespec---a byte specifier.

integer---an integer.

generalized-boolean---a generalized boolean.

Description:

Returns true if any of the bits of the byte in integer specified by bytespec is non-zero; otherwise returns false.

Examples:

     (ldb-test (byte 4 1) 16) =>  true
     (ldb-test (byte 3 1) 16) =>  false
     (ldb-test (byte 3 2) 16) =>  true

Side Effects: None.

Affected By: None.

Exceptional Situations: None.

See Also:

byte, ldb, zerop

Notes:

     (ldb-test bytespec n) ==
     (not (zerop (ldb bytespec n))) ==
     (logtest (ldb bytespec -1) n)

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