Bitwise Functions

These functions operate on the bit string which an integer is made of.

Function: lsh number count

This function bit-shifts the integer number count bits to the left, if count is negative number is shifted to the right instead.

(lsh 1 8)
    => 256

(lsh 256 -8)
    => 1

Function: ash number count

Similar to lsh except that an arithmetical shift is done, this means that the sign of number is always preserved.

(ash 1 8)
    => 256

(ash -1 2)
    => -4

Function: logand number1 &rest numbers

This function uses a bit-wise logical `and' operation to combine all its arguments (there must be at least one argument).

(logand 15 8)
    => 8

(logand 15 7 20)
    => 4

Function: logior number1 &rest numbers

Uses a bit-wise logical `inclusive-or' to combine all its arguments (there must always be at least one argument).

(logior 1 2 4)
    => 7

Function: logxor number1 &rest numbers

Uses a bitwise logical `exclusive-or' to combine all its arguments (there must be at least one).

(logxor 7 3)
    => 4

Function: lognot number

This function inverts all the bits in number.

(lognot 0)
    => -1

(lognot 2)
    => -3

(lognot -1)
    => 0

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