Terser为什么不压缩这一段代码是因为副作用

上代码：

import  * as ute from 'bbbb';console.log(ute.cube(65,2));console.log(ute.func1f(89));

bbbb:

export {cube,addX1,addX2,addX3,addX4} from './Math.js';export {ut_a} from './ut.js';

Math.js:

export function square(x) {    return x * x;}export function cube(x) {    return x * x * x* eval('addX3')();}export function addX1(x) {    return x + Math.random() * 1111111111;}export function addX2(x) {    return x + Math.random() * 2222222222;}export function addX3(x) {    return x + Math.random() * 3333333333;}export function addX4(x) {    return x + Math.random() * 45444444444;}

经过WEBPACK处理后，变成如下：

(window["webpackJsonp"] = window["webpackJsonp"] || []).push([["zpageATS"],{/***/ "./node_modules/bbbb/Math.js":/***/ (function(module, __webpack_exports__, __webpack_require__) {"use strict";/* unused harmony export square *//* harmony export (binding) */ __webpack_require__.d(__webpack_exports__, "a", function() { return cube; });/* unused harmony export addX1 *//* unused harmony export addX2 *//* unused harmony export addX3 *//* unused harmony export addX4 */function square(x) {    return x * x;}function cube(x) {    return x * x * x* eval('addX3')();}function addX1(x) {    return x + Math.random() * 1111111111;}function addX2(x) {    return x + Math.random() * 2222222222;}function addX3(x) {    return x + Math.random() * 3333333333;}function addX4(x) {    return x + Math.random() * 45444444444;}/***/ }),/***/ "./node_modules/bbbb/index.js":/***/ (function(module, __webpack_exports__, __webpack_require__) {"use strict";/*import * as ute from './Math.js';export {ute};*//***/ }),/***/ "./pageATS.js":/***/ (function(module, __webpack_exports__, __webpack_require__) {"use strict";__webpack_require__.r(__webpack_exports__);/* harmony import */ var bbbb__WEBPACK_IMPORTED_MODULE_0__ = __webpack_require__("./node_modules/bbbb/Math.js");/* harmony import */ var bbbb__WEBPACK_IMPORTED_MODULE_1__ = __webpack_require__("./node_modules/bbbb/index.js");console.log(bbbb__WEBPACK_IMPORTED_MODULE_0__[/* cube */ "a"](65,2));console.log(bbbb__WEBPACK_IMPORTED_MODULE_1__["func1f"](89));/***/ })},[["./pageATS.js","pageInit"]]]);

TERSER后：

(window.webpackJsonp = window.webpackJsonp || []).push([    ["zpageATS"], {        "./node_modules/bbbb/Math.js": function(module, __webpack_exports__, __webpack_require__) {            "use strict";            function square(n) {                return n * n            }            function cube(x) {                return x * x * x * eval("addX3")()            }            function addX1(n) {                return n + 1111111111 * Math.random()            }            function addX2(n) {                return n + 2222222222 * Math.random()            }            function addX3(n) {                return n + 3333333333 * Math.random()            }            function addX4(n) {                return n + 45444444444 * Math.random()            }            __webpack_require__.d(__webpack_exports__, "a", (function() {                return cube            }))        },        "./node_modules/bbbb/index.js": function(n, e, o) {},        "./pageATS.js": function(n, e, o) {            "use strict";            o.r(e);            var u = o("./node_modules/bbbb/Math.js"),                a = o("./node_modules/bbbb/index.js");            console.log(u.a(65, 2)), console.log(a.func1f(89))        }    },    [        ["./pageATS.js", "pageInit"]    ]]);

肉眼可见有代码并没有被shaking掉

而如果Math.js:换成这个呢？

export function square(x) {    return x * x;}export function cube(x) {    return x * x * x* 67;}export function addX1(x) {    return x + Math.random() * 1111111111;}export function addX2(x) {    return x + Math.random() * 2222222222;}export function addX3(x) {    return x + Math.random() * 3333333333;}export function addX4(x) {    return x + Math.random() * 45444444444;}

TERSER前：

(window["webpackJsonp"] = window["webpackJsonp"] || []).push([["zpageATS"],{/***/ "./node_modules/bbbb/Math.js":/***/ (function(module, __webpack_exports__, __webpack_require__) {"use strict";/* unused harmony export square *//* harmony export (binding) */ __webpack_require__.d(__webpack_exports__, "a", function() { return cube; });/* unused harmony export addX1 *//* unused harmony export addX2 *//* unused harmony export addX3 *//* unused harmony export addX4 */function square(x) {    return x * x;}function cube(x) {    return x * x * x* 67;}function addX1(x) {    return x + Math.random() * 1111111111;}function addX2(x) {    return x + Math.random() * 2222222222;}function addX3(x) {    return x + Math.random() * 3333333333;}function addX4(x) {    return x + Math.random() * 45444444444;}/***/ }),/***/ "./node_modules/bbbb/index.js":/***/ (function(module, __webpack_exports__, __webpack_require__) {"use strict";/*import * as ute from './Math.js';export {ute};*//***/ }),/***/ "./pageATS.js":/***/ (function(module, __webpack_exports__, __webpack_require__) {"use strict";__webpack_require__.r(__webpack_exports__);/* harmony import */ var bbbb__WEBPACK_IMPORTED_MODULE_0__ = __webpack_require__("./node_modules/bbbb/Math.js");/* harmony import */ var bbbb__WEBPACK_IMPORTED_MODULE_1__ = __webpack_require__("./node_modules/bbbb/index.js");console.log(bbbb__WEBPACK_IMPORTED_MODULE_0__[/* cube */ "a"](65,2));console.log(bbbb__WEBPACK_IMPORTED_MODULE_1__["func1f"](89));/***/ })},[["./pageATS.js","pageInit"]]]);

TERSER后：

(window.webpackJsonp = window.webpackJsonp || []).push([    ["zpageATS"], {        "./node_modules/bbbb/Math.js": function(n, o, e) {            "use strict";            function s(n) {                return n * n * n * 67            }            e.d(o, "a", (function() {                return s            }))        },        "./node_modules/bbbb/index.js": function(n, o, e) {},        "./pageATS.js": function(n, o, e) {            "use strict";            e.r(o);            var s = e("./node_modules/bbbb/Math.js"),                b = e("./node_modules/bbbb/index.js");            console.log(s.a(65, 2)), console.log(b.func1f(89))        }    },    [        ["./pageATS.js", "pageInit"]    ]]);

可见该移除的都已经被完美移除了，

差别就在这里：