gulpfile.js:

const gulp = require("gulp");
const concat = require("gulp-concat");
const sass = require("gulp-sass")(require("sass"));
const ts = require("gulp-typescript");
const del = require("del");

const outputFolder = "dist";

const cleanWorkload = (cb) => {
  del.sync([outputFolder]);
  cb();
};

/* WORKLOADS */
const scssWorkload = () => gulp.src("src/scss/index.scss").pipe(sass()).pipe(gulp.dest(outputFolder));
const tsWorkload = () =>
  gulp
    .src("src/ts/**/*.ts")
    .pipe(
      ts({
        module: "es6",
        target: "es5",
        lib: ["DOM", "DOM.Iterable", "ESNext"],
      })
    )
    .pipe(concat("tree.js"))
    .pipe(gulp.dest(outputFolder));

/* DEFAULT */
const directCompilation = gulp.parallel(scssWorkload, tsWorkload);
gulp.task("default", gulp.series(cleanWorkload, directCompilation));

/* WATCH */
gulp.task("watch", () => {
  gulp.watch("src/scss/**/*.scss", scssWorkload);
  gulp.watch("src/ts/**/*.ts", tsWorkload);
});

源文件的代码段：

import ElementCreator from "./helpers/ElementCreator";
import Branch from "./types/Branch.interface";
import BranchDescription from "./types/BranchDescription.interface";
import TreeConfig from "./types/TreeConfig.interface";

export default class Tree {
  private $el: HTMLElement;
  private branches: Branch[];
...

问题是，当我运行gulp时，输出文件包含以下内容：

import ElementCreator from "./helpers/ElementCreator";
var Tree = /** @class */ (function () {
    function Tree(config) {
...

var ElementCreator = /** @class */ (function () {
    function ElementCreator() {
    }
...

所以浏览器会抱怨ElementCreator已经被声明了
我如何告诉gulp删除所有这些import语句，因为这些文件无论如何都是连接在一起的？