在 es6 中使用 rollup.js

Question

This is a follow-up question to How to set up rollup.js with a d3 plugin? .

I have little dummy module foo.js:

//.src/foo.js
import * as d3 from "d3";

export default function() {
  return d3.select("body").append("div").text(42); 
};

and an index.js:

export {default as foo} from "./src/foo";

for which I can apply rollup with the following rollup.config.js:

// rollup.config.js
import babel from "rollup-plugin-babel";
import * as meta from "./package.json";

export default {
  input: "index.js",
  external: ["d3"],
  output: {
    file: `build/${meta.name}.js`,
    name: "d3",
    format: "umd",
    indent: false,
    extend: true,
    // banner: `// ${meta.homepage} v${meta.version} Copyright ${(new Date).getFullYear()} ${meta.author}`,
    globals: {d3: "d3"},
    plugins: [
      babel({
        exclude: "node_modules/**"})
    ]
  },
};

This works fine. However, if I add a es6 command like "const" to foo.js:

import * as d3 from "d3";

export default function() {
  const num = 42;
  return d3.select("body").append("div").text(num); 
};

I get an ERROR: Unexpected token: keyword «const» at JS_Parse_Error.get (eval at...)

How do I have to update my rollup.config.js to make it work?

Answer 1

The error that came up is unrelated to rollup.js. I missed that I run uglify-js which caused that problem...