bit slicing

bitslice.js

// Binary bit slice from the right to the left
//  msb: n-th more significant bit from the right (inclusive)
//  lsb: n-th less signnificant bit from the right (inclusive)
//
//  bitSlice(x, 2, 0) - last 3 bits of a number
//  bitSlice(x, 3, 2) - 4th and 3rd least significant bits
function bitSlice(n, msb, lsb) {
    return (n & ((1 << (msb + 1)) - 1)) >> lsb
}