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index—a non-negative integer.
integer—an integer.
generalized-boolean—a generalized boolean.
logbitp
is used to test the value of a particular bit
in integer, that is treated as if it were binary.
The value of logbitp
is true if the bit in integer
whose index is index (that is, its weight is 2^index)
is a one-bit; otherwise it is false.
Negative integers are treated as if they were in two's-complement notation.
(logbitp 1 1) → false (logbitp 0 1) → true (logbitp 3 10) → true (logbitp 1000000 -1) → true (logbitp 2 6) → true (logbitp 0 6) → false
Should signal an error of type type-error
if index is not a non-negative integer.
Should signal an error of type type-error
if integer is not an integer.
(logbitp k n) ≡ (ldb-test (byte 1 k) n)