logtest (ANSI and GNU Common Lisp Document)

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#### 12.2.65 logtest [Function]

`logtest` integer-1 integer-2 ⇒ generalized-boolean

#### Arguments and Values::

integer-1—an integer.

integer-2—an integer.

generalized-boolean—a generalized boolean.

#### Description::

Returns true if any of the bits designated by the 1’s in integer-1 is 1 in integer-2; otherwise it is false. integer-1 and integer-2 are treated as if they were binary.

Negative integer-1 and integer-2 are treated as if they were represented in two’s-complement binary.

#### Examples::

     (logtest 1 7) ⇒  true
     (logtest 1 2) ⇒  false
     (logtest -2 -1) ⇒  true
     (logtest 0 -1) ⇒  false

#### Exceptional Situations::

Should signal an error of type type-error if integer-1 is not an integer. Should signal an error of type type-error if integer-2 is not an integer.

#### Notes::

     (logtest x y) ≡ (not (zerop (logand x y)))