bits operation dev and tested

src/utils.ts

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+import { Uint16, Uint32 } from "./types";
+
+
+export const getUint32 = (lsb: Uint16, msb: Uint16): Uint32 => Uint32Array.from([(msb << 16) | lsb])[0]
+
+export const getBit = (num: number, bit: number): boolean => (num >>> bit) % 2 != 0

tests/utils.test.ts

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+import { test, expect } from 'vitest'
+import * as utils  from '../src/utils'
+
+test('getUint32', () => {
+  const a = 0b1111_1010_0101_0000
+  const b = 0b1010_0101_0000_1111
+  const b_a = Uint32Array.from([0b1010_0101_0000_1111_1111_1010_0101_0000])[0]
+  const d = utils.getUint32(a, b)
+  expect(d).toBe(b_a)
+})
+
+test('getBit', () => {
+  const bits = 0b1010_1010_1010_1010
+  for (let i = 0; i < 16; i++) {
+    const bit = utils.getBit(bits, i)
+    if ((i % 2) === 0) {
+      expect(bit).toBeFalsy()
+    } else {
+      expect(bit).toBeTruthy()
+    }
+  }
+})