union.js

import * as XDR from '../src';

let xdr = XDR.config((xdr) => {
  xdr.union('Result', {
    switchOn: xdr.lookup('ResultType'),
    switches: [
      ['ok', xdr.void()],
      ['error', 'message']
    ],
    // defaultArm: xdr.void(),
    arms: {
      message: xdr.string(100)
    }
  });

  xdr.enum('ResultType', {
    ok: 0,
    error: 1,
    nonsense: 2
  });
});

let r = xdr.Result.ok();
r.set('error', 'this is an error');
r.message(); // => "this is an error"
r.get('message'); // => "this is an error"

r.set(xdr.ResultType.ok());
r.get(); // => undefined

// r.set("nonsense");
r.get(); // => undefined

let output = r.toXDR();
let parsed = xdr.Result.fromXDR(output);

console.log(r);
console.log(r.arm());
console.log(parsed);