Cannot redeclare let variable in Safari

After upgrading to babili 0.1.2 following error appears in Safari 10.1 (running ES6 native): SyntaxError: Cannot declare a let variable twice: 'e'.. It happens on fragments like this (after minify I have a lot of this):

function a(e) {
  let e = 1;
  console.log(e);
}
a(2);

// Real life minify result:

  function Ge(e, t) {
    const n = e.toLowerCase(),
          a = n.split(/\s+/),
          r = [];

    for (let e = 0, n = 0; n < t && e < a.length; n += a[e].length, e++) r.push(a[e].split('').map((e) => e.normalize('NFKD').charAt(0)).filter((e) => /[A-z]/.test(e)).join(''));
    return r.join('-');
  }

and it seems for me that Safari counts function parameters as declared by let. Neither Chrome, Firefox or Edge have such problem. Is there any workaround apart of switching off minify (as I’m forced to do now)?

[btmills]

We hit this bug at work. I’ve put together what I hope is a successful workaround and filed a PR: #567.

[tinovyatkin]

@boopathi That’s great, but the bug is already in several shipped versions, so, I think it must be avoided for a next couple of years… No fix?